Section 2.1. Choosing Components


2.1. Choosing Components

The biggest advantage of building your own PC is that you can choose which components to use. If you buy a cookie-cutter system from Dell or HP, most of the decisions are made for you. You can specify a larger hard drive, more memory, or a different monitor, but the range of options is quite limited. Want a better power supply, a quieter CPU cooler, or a motherboard with built-in FireWire and enhanced RAID support? Tough luck. Those options aren't on the table.

When you build from scratch, you get to choose every component that goes into your system. You can spend a bit more here and a bit less there to get exactly the features and functions you want at the best price. It's therefore worth devoting some time and effort to component selection, but there are so many competing products available that it's difficult to separate the marketing hype from reality.

On your own, you might find yourself struggling to answer questions like, "Should I buy a Seagate hard drive or a Western Digital?" (hint: Seagate), or "Does Sony or HP make the best DVD writers?" (hint: neither; Plextor makes the best optical drives, but there are "bargain" brands that are quite good). We've done all that research for you, and the following sections in conjunction with our online forums distill what we've learned in testing and using hundreds of products over many years.

We recommend products by brand name, and we don't doubt that some people will take issue with some of our recommendations. We don't claim that the products we recommend are "best" in any absolute sense, because we haven't tested every product on the market and because "best" is inherently subjective. What's "best" for us may be just "very good" from your point of view, but it almost certainly won't be "awful."

So, keeping all of that in mind, the following sections describe the products we recommend.

2.1.1. Case

The case (or chassis) is the foundation of any system. Its obvious purpose is to support the power supply, motherboard, drives, and other components. Its less-obvious purposes are to contain the radio-frequency interference produced by internal components; to ensure proper system cooling; and to subdue the noise produced by the power supply, drives, fans, and other components with moving parts.

A good case performs all of these tasks well, and is a joy to work with. It is strongly built and rigid. Adding or removing components is quick and easy. All the holes line up. There are no sharp edges or burrs. A bad case is painful to work with, sometimes literally. It may have numerous exposed razor-sharp edges and burrs that cut you even if you're careful. It is cheaply constructed of flimsy material that flexes excessively. Tolerances are very loose, sometimes so much so that you have to bend sheet metal to get a component to fit, if that is even possible. Using a cheap case is a sure way to make your system-building experience miserable.

BTX

The latest case form factors are BTX (Balanced Technology eXtended) and its smaller variants microBTX and picoBTX, which until late 2006 Intel had been pushing strongly as the eventual replacement for ATX and microATX. Relative to ATX-family cases, BTX-family cases offer superior ventilation and cooling and other improvements. BTX-family cases use ATX-family power supplies, but are physically incompatible with ATX-family motherboards.

As of August 2006, when we completed the final draft manuscript for this book, Intel had announced its intention to convert fully to BTX in 2007 and 2008, abandoning the ATX standard. In mid-October 2006, as this book was about to go to press, Intel abruptly reversed course, announcing that it would cease producing BTX components in 2007, and return to producing only ATX and microATX products. Most industry observers believe that this abrupt change was caused by Intel's fast transition from the hot-running, power-hungry Pentium 4/D architecture to the cool, low-power Core 2 architecture. Suddenly, Intel processors no longer had a heat problem, and BTX was a solution in search of a problem.


Use the following guidelines when choosing a case:

  • Choose the proper size case, taking into account the original configuration and possible future expansion. For a general-purpose system, choose a mini- or mid-tower case. For a small PC, choose a microATX case. Choose a case that leaves at least one drive bayideally a 5.25" external bayfree for later expansion.

  • Get a case with supplemental cooling fans, or space to add them. Heat is the enemy of processors, memory, drives, and other system components. Cooler components last longer and run more reliably.

The cases we recommend are listed at http://www.hardwareguys.com/picks/cases.html.

2.1.2. Power Supply

The power supply is one of the most important components in a PC, and yet most people give it little consideration. In addition to providing reliable, stable, closely-regulated power to all system components, the power supply draws air through the system to cool it. A marginal or failing power supply can cause many problems, some of which are very subtle and difficult to track down. Most problems are not subtle, however. A poor or marginal power supply is likely to cause system crashes, memory errors, and data corruption, and may fail catastrophically, taking other system components with it.

Use the following guidelines to choose a power supply appropriate for your system:

  • Above all, make sure the power supply you buy fits your case and has the proper connectors for your motherboard. Most cases use ATX power supplies, and any ATX power supply fits any ATX case. SFF and microATX cases often use SFX or proprietary power supplies. We avoid using those whenever possible.

  • Size your power supply according to the system configuration. For an entry-level system, install a 300W or larger power supply. For a mainstream system, install a 400W or larger power supply. For a high-performance system, install a 500W or larger power supply. If you're installing dual video adapters in an nVIDIA SLI (Scalable Link Interface) or AMD/ATi CrossFire configuration, make sure to use a power supply that is certified for operation with dual video adapters.

  • Buy only an ATX12V 2.0 or higher compliant power supply.

  • Make sure the power supply provides Serial ATA power connectors.

The power supplies we recommend are listed at http://www.hardwareguys.com/picks/power.html.

2.1.3. Processor

Most people spend too much time dithering about which processor to install. The two choices you have to make are, first, Intel versus AMD, and, second, how much to spend. Here are the considerations for each of the processor price ranges:


Low-end (under $150)

At the bottom of this rangesub-$100 processorsinexpensive AMD Sempron models are generally faster than comparably-priced Intel Celerons. At the upper end of this range are the least expensive processors that we consider mainstream modelsthe slower Athlon 64, Athlon 64 X2, Pentium 4, and Pentium D processors, all of which offer similar price/performance ratios.


Midrange ($150 to $250)

This is the mainstream. The bottom half of this range includes fast Pentium D and Athlon 64 X2 processors, any of which are good choices for a mainstream system, as well as the entry-level Core 2 Duo processors. At the upper end of this range are the fastest Pentium D and Athlon 64 X2 processors and midrange Core 2 Duo models. Midrange processors as a group are generally noticeably faster than low-end processors and cost only a little more, while at the same time they are only a bit slower than high-end processors and cost a lot less.


High-end ($250+)

AMD is no longer competitive in this segment. At the lower end, this range is the realm of midrange Core 2 Duo models. At the high endwhich may approach or exceed $1,000you'll find the Intel Core 2 Duo Extreme Edition. This range is characterized by a rapidly decreasing bang-for-the-buck ratio. A $150 processor might be 50% faster than a $75 processor, but a $500 processor may be only 10% faster than a $250 processor, and a $1,000 processor only 5% faster than a $500 one.

Also consider the following issues when you choose a processor:

  • Even the slowest current processor more than suffices for office productivity applications. If you never load the system heavily, you'll not notice much difference between an inexpensive processor and a more expensive model.

  • Low-end processors are hampered by small secondary caches, which cripple performance, particularly if you work with large data sets, such as multimedia, graphics, or video.

  • Processors in the "sweet spot" range$150 to $225 for a retail-boxed processorusually represent the best bang for the buck.

  • Buy the processor you need initially, rather than buy a slower processor now and plan to upgrade later. Processor upgrades, AMD and Intel, are a minefield of compatibility issues.

The processors we recommend are listed at http://www.hardwareguys.com/picks/processors.html.

THE GREAT PROCESSOR SHAKEUP

In July 2006, Intel introduced its long-awaited Core 2 Duo line of processors and obsoleted its existing single-core Pentium 4 processors and dual-core Pentium D processors overnight. At introduction, even the entry-level $185 Core 2 Duo E6300 processor was as fast as existing AMD and Intel processors that had been selling for $350 to $600. In addition to very high performance, Core 2 Duo processors feature very low power consumption and correspondingly low heat production. For Core 2 Duo, Intel claims a 40% increase in performance at 40% lower power consumption, and our testing confirms those claims.

Core 2 Duo was a devastating blow to AMD's single-core Athlon 64 and dual-core Athlon 64 X2 processor line. AMD took a meat-ax to its processor price list, cutting prices on many models by 60% or more. Even that wasn't enough to give AMD price/performance parity with Core 2 Duo. In effect, Core 2 Duo knocked AMD back into K6 days, when all it had to sell was "value" processors. Or, more accurately, AMD is now selling what we consider "mainstream" and "performance" processors at "value" prices. Intel again owns the high end, and is likely to keep that crown at least through late 2007. In the interim, Intel and AMD will compete strongly in the midrange $150 to $250 segment, with Intel selling its slowest processors in that price range, and AMD selling its fastest. All of us benefit, because we're now able to get what amounts to a performance processor for a mainstream price.

As we write this in August 2006, Intel's plans for the Core 2 processor line are unclear. We expect Intel to release single-core Core 2 Solo models in late 2006 as a replacement for the aging Celeron series. If that occurs, Intel will own the low-end segment as well as the midrange and high-end segments unless AMD makes extraordinary pricing cuts on its single-core Athlon 64 line. We expect that to happen as well, because otherwise AMD will find itself unable to sell any processors.


Whither Pentium D?

Although Intel has not yet discontinued the Pentium D, and in fact introduced new models in July 2006, Pentium D is really just a bridge processor. Intel will continue to offer it as they ramp up Core 2 Duo production, but will almost certainly discontinue it as soon as they are able to meet demand for Core 2 Duo. While it remains available, which will probably be well into 2007, Pentium D remains an excellent choice. Intel has priced it competitively in terms of price/performance against the Core 2 Duo, and certainly against the AMD Athlon 64 X2. The only downside of Pentium D is that it draws a lot of power and produces a lot of heat. Still, that can be dealt with, so don't rule out Pentium D when you're designing your own system.


2.1.4. Heatsink/Fan Units (CPU Coolers)

Modern processors consume 50W to 100W or more. Nearly all systems deal with the resulting heat by placing a massive metal heatsink in close contact with the processor and using a small fan to draw air through the heatsink fins. This device is called a heatsink/fan (HSF) or CPU cooler. Use the following guidelines when choosing an HSF:

  • Make certain the HSF is rated for the exact processor you use. An HSF that physically fits a processor may not be sufficient to cool it properly. In particular, be careful with newer Intel Pentium 4 and Pentium D processors, which produce much more heat than the earlier models that ran at similar speeds.

  • Make sure the HSF is usable with your motherboard. Some HSFs are incompatible with some motherboards because clamping the HSF into position may crush capacitors or other components near the processor socket.

  • Pay attention to noise ratings. Some high-efficiency HSFs designed for use by overclockers and other enthusiasts have very noisy fans. Other HSFs are nearly silent.

  • Use the proper thermal compound. When you install an HSF, and each time you remove and replace it, use fresh thermal compound to ensure proper heat transfer. Thermal compound is available in the form of viscous thermal "goop" and as phase-change thermal pads, which melt as the processor heats up and solidify as it cools down. Make sure that the thermal compound you use is approved by the processor maker.

The CPU coolers we recommend are listed at http://www.hardwareguys.com/picks/cpu-coolers.html.

2.1.5. Motherboard

The motherboard is the main logic board around which a PC is built. The motherboard is the center of the PC in the sense that every system component connects to the motherboard, directly or indirectly. The motherboard you choose determines which processors are supported, how much and what type of memory the system can use, what type of video adapters can be installed, the speed of communication ports, and many other key system characteristics.

Use the following guidelines when choosing a motherboard:

  • For a general-purpose system, choose an ATX motherboard. For a small system, a microATX motherboard may be a better choice, although using the smaller form factor has several drawbacks, notably giving up several expansion slots and making it more difficult to route cables and cool the system.

  • For a Pentium D or Core 2 Duo system, choose a Socket 775 (Socket T) motherboard that is compatible with your choice of processor. For an Athlon 64 X2 system, choose a Socket AM2 motherboard.

  • For an Intel processor, choose an Intel or ASUS motherboard that uses an Intel 946/955X/963/965/975X-series chipset. For an AMD processor, choose an ASUS motherboard that uses an nVIDIA nForce 5-series chipset.

  • Make sure the motherboard supports the exact processor you plan to use. Just because a motherboard supports a particular processor family doesn't mean it supports all members of that family. You can find this information on the motherboard maker's web site or in the release notes to the BIOS updates. It's also important to know exactly what revision of the motherboard you have, because processor support may vary by motherboard revision level.

  • Make sure the motherboard supports the type and amount of memory you need. Do not make assumptions about how much memory a motherboard supports. Check the documentation to find out what specific memory configurations are supported.

  • Before you choose a motherboard, check the documentation and support that's available for it, as well as the BIOS and driver updates available. Frequent updates indicate that the manufacturer takes support seriously.

The motherboards we recommend are listed at http://www.hardwareguys.com/picks/motherboards.html.

2.1.6. Memory

The only real decisions are how much memory to install, what size and type of modules to use, and what brand to buy. Consider the following factors when choosing memory modules (DIMMs):

  • For budget systems, install no less than 512 MB. If the system will run Windows Vista, install 1 GB or more. For mainstream systems, install 1 GB or more. For performance systems, workstations, and multimedia/graphics systems, install 2 GB or more. If you use a Core 2 Duo, Pentium D or Athlon 64 X2 dual-core processor, double these amounts.

  • Memory manufacturers like Crucial (http://www.crucial.com), Kingston (http://www.kingston.com), Corsair (http://www.corsairmemory.com), and Mushkin (http://www.mushkin.com) provide online memory configurators that allow you to enter the brand and model of your motherboard and return a list of compatible memory modules. Before you buy memory, use these configurators to make sure the memory you order is compatible with your particular motherboard.

  • For motherboards that use 184-pin DDR memory, buy only PC3200 or faster DDR-SDRAM memory modules. Choose modules that support fast CAS latency timings only if they cost little or no more than modules that support standard timings.

  • For motherboards that use 240-pin DDR2 memory, buy DDR2 memory modules of at least the speed required by your motherboard/processor combination. DDR2 memory is available in PC2 3200, PC2 4200, PC2 5300, PC2 6400, and PC2 8000 variants. Choose the fastest modules that do not sell at a significant price premium over slower modules. Once again, choose modules that support fast CAS latency timings only if they cost little or no more than modules with standard timings.

  • For higher performance, use DIMMs in pairs to enable dual-channel memory operation.

  • It's generally less expensive to buy a given amount of memory in fewer modules. For example, if you are installing 2 GB of memory, two 1 GB DIMMs will probably cost less than four 512 MB DIMMs. Using fewer but larger DIMMs also preserves memory slots for future expansion. However, the largest capacity modules often sell at a substantial premium. For example, a 2 GB DIMM may cost five times as much as a 1 GB DIMM, rather than only twice as much.

  • Verify the memory configurations supported by your motherboard. For example, a particular motherboard may support 1 GB DIMMs, but not 2 GB DIMMs. One motherboard may support 1 GB DIMMs in all four of its memory slots, but another may support 1 GB DIMMs in only two of its four slots. Check the motherboard documentation to determine the memory configurations your chosen motherboard supports.

  • Nonparity memory modules provide no error detection or correction. ECC modules detect and correct most memory errors, but are slower and more expensive than nonparity modules. Use ECC memory if you install more than 2 GB of memory and the motherboard supports ECC memory. For 2 GB or less, use nonparity modules.

The memory modules we recommend are listed at http://www.hardwareguys.com/picks/memory.html.

2.1.7. Floppy Disk Drive (FDD)

Every time we build a PC without an FDD we regret doing it when we need to load a driver from floppy. (But we keep doing it anyway...) Accordingly, we recommend installing an FDD. At $8 or so, it's cheap insurance. If you want an FDD, buy any brand. FDDs are commodity items, and the brand makes little difference. If you're short on external drive bays and want both an FDD and a card reader, install a combination FDD/card reader such as the Mitsumi FA402A.

ADVICE FROM BRIAN BILBREY

Almost all new motherboards support booting from a USB floppy these days. Buy one of these, and your days of installing a new FDD in a box, or migrating an FDD from a retired system to a new one are over.


2.1.8. Hard Drive

It's easy to choose a good hard drive. Several manufacturers produce drives at similar price points for a given size and type of drive. That said, we prefer Seagate hard drives because they are fast, quiet, cool-running, and competitively-priced, and because we and our readers have experienced poor reliability with drives made by some other manufacturers.

Compatibility is not an issue for hard drives. Hard drives are plug-and-play devices. Any recent hard drive coexists peacefully with any other recent hard drive or optical drive, regardless of manufacturer. (But see the warning about Serial ATA optical drives in the next section.)

Use the following guidelines when you choose a hard disk:

  • Hard drives are available in standard ATA (Parallel ATA or PATA) and Serial ATA (SATA) interfaces. PATA drives are suitable only for upgrading older systems that lack SATA interfaces. For a new system, choose a drive that uses the SATA interface. Choose a model that supports the 3.0 Gb/s SATA interfacewhich is often (incorrectly) described as SATA-IIand native command queuing (NCQ).

  • It's tempting to buy the highest-capacity drive available, but high-capacity drives often cost more per gigabyte than midrange drives, and the highest-capacity drives are often slower than midrange models. Decide what performance level and capacity you need, and then buy a drive that meets those requirements. Choose the model based on cost per gigabyte. You may need to buy the largest drive available despite its higher cost per gigabyte and slower performance, simply to conserve drive bays and ATA channels.

  • Choose a 7,200 RPM SATA drive for a general-purpose system. 10,000 RPM drives cost more than 7,200 RPM models, are not all that much faster, and are much noisier and hotter running than 7,200 RPM models.

  • Get a model with larger buffer/cache if it doesn't cost much more. Some drives are available in two versions that differ only in buffer size. One might have a 2 MB buffer and the other an 8 MB buffer. The larger buffer is worth paying a few extra dollars for.

The hard drives we recommend are listed at http://www.hardwareguys.com/picks/harddisk.html.

2.1.9. Optical Drive

Every system needs an optical drive of some sort, if only for loading software. There are several types of optical drives available. Some can use only CDs, which typically store about 700 MB of data. Other optical drives can use DVDs, which typically store between 4,700 MB and 8,500 MB of data. CD-ROM and DVD-ROM drives are read-only (the "ROM" part of the name). CD writers and DVD writers (also called burners or recorders) can write optical discs as well as read them. DVD is backward compatible with CD, which means that a DVD drive can also read CD discs, and all DVD writers can also write CD discs.

CD drive speeds are specified as a multiple of the 150 KB/s audio CD rate, which is called 1X. For example, a 52X CD drive transfers data at 52 times 150 KB/s, or 7,800 KB/s. DVD drives use a different "X-factor." A 1X DVD drive transfers data at about 1.321 MB/s, or about nine times faster than a 1X CD drive.

Choose an optical drive for your system based on the capabilities you need and the price you are willing to pay. In the past, there were many different types of optical drives, with a wide range of prices and capabilities, including such variants as hybrid DVD-ROM/CD writers. Most of those drive types have fallen by the wayside, victims of the rapidly declining prices of more capable drives. Nowadays, only two optical drive types make sense for use in new systems.


DVD-ROM drive

DVD-ROM drives read CD and DVD discs, cannot write discs, and sell for $20 or less. Install a DVD-ROM drive only when budget is the top priority and you don't need a drive that can write discs. Choose any current model made by Lite-On, Mitsumi, NEC, Samsung, or Toshiba. If you need to read writable DVD discs, make sure the model you choose explicitly lists compatibility with the formats you use. If you need to read DVD-RAM discs, buy a Toshiba model. Otherwise, buy on price.


DVD writer

DVD writers read and write both CDs and DVDs. Inexpensive DVD writers such as those made by BenQ and NEC sell for $35, and are perfectly acceptable for casual use. Midrange and premium models made by Plextor are a better choice for heavy use and when reliability counts, such as making backups.

DON'T BUY AN SATA OPTICAL DRIVE

Nearly all optical drives use the PATA interface. A few models are available with the SATA interface, but we suggest you avoid those. SATA optical drives are plagued with compatibility problems. If you must have an SATA optical drive, make absolutely sure it is certified to be compatible with the exact motherboard model you use.


DON'T BUY A PATA OPTICAL DRIVE

Of course, if you're building an Intel Core 2 system based on a motherboard built around the Intel ICH8 south bridge, you have no choice. ICH8 does not provide PATA interfaces, so your only option is to use an SATA optical drive. The only SATA model we can recommend is the Plextor PX-755SA. Just make sure the motherboard is explicitly listed on Plextor's supported motherboards list.


The optical drives we recommend are listed at http://www.hardwareguys.com/picks/optical.html.

2.1.10. Video Adapter

The video adapter, also called a graphics adapter, renders video data provided by the processor into a form that the monitor can display. Many motherboards include embedded (integrated) video adapters. You can also install a standalone video adapter, also called a video card or graphics card, in a motherboard expansion slot. Keep the following in mind when you choose a video adapter:

  • Unless you run graphics-intensive games, 3D graphics performance is unimportant. Any recent video adapter is more than fast enough for business applications and casual gaming.

  • Choose integrated video unless there is good reason not to. Integrated video adds little or nothing to the price of a motherboard, and generally suffices for anyone except hardcore gamers or those with other special video requirements. Make sure any motherboard you buy allows integrated video to be disabled and provides an AGP or PCI Express slot. That way, you can upgrade the video later if you need to.

  • Make sure that the video adapter you choose uses the type of interface provided by your motherboard. Older motherboards and some current models use the obsolescent AGP (Accelerated Graphics Port) interface. Most current motherboards use the newer PCI Express (PCIe) interface. When you buy a motherboard for a new system, always choose a PCIe model unless you already have an AGP video adapter that you want to migrate to the new system.

    WHAT ABOUT VISTA AND AERO GLASS?

    Much has been made of the fact that Windows Vista is the first version of Windows to use a 3D graphical interface. While it's true that the Aero Glass interface requires 3D graphics support, we have verified that recent integrated video adapters including Intel GMA 950, Intel GMA 3000, and nVIDIA 6100/6150 have sufficiently powerful 3D acceleration to handle Aero Glass. Any video adapter, standalone or integrated, that supports DirectX 9 and PS (Pixel Shader) 2.0 and has 128 MB of memory (on-board or shared) should suffice to run Aero Glass, albeit not with top performance.


    ADVICE FROM BRIAN JEPSON

    And even then, trying to keep the old one locks you into some unpleasant trade-offs. I had a great AGP adapter that I handed down to my brother because I couldn't find a decent AGP motherboard that supported a dual core Pentium. It seems that trying to get AGP support on a modern system leads to some motherboards that are real mongrels in terms of chipsets.


  • Make sure that the video adapter you choose (or the integrated video on your motherboard) provides the type of video output connector you need. CRT monitors and some LCD displays use the 15-pin analog VGA connector; other LCD displays use the digital DVI connector.

  • If you plan to use dual displays, make sure that your integrated video or video adapter supports dual displays, and that it provides the type of video connectors you need for both displays. Note that some video adapters provide one analog and one digital video connector, but allow only one of those to operate at a time. The most flexible choice is a card with dual DVI-I hybrid video connectors, which support both analog and digital displays.

    ADVICE FROM JIM COOLEY

    Even if you plan to use a separate video adapter, having integrated video available is a good diagnostic resource. For that reason alone I'd never buy a board without one.


  • If you need a 3D graphics adapter, don't overbuy. A $400 video adapter is faster than a $100 adapter, but nowhere near four times faster. As with other PC components, the bang-for-the-buck ratio drops quickly as the price climbs. If you need better 3D graphics performance than integrated video provides but you don't have much in the budget for a video adapter, look at "obsolescent" 3D video adaptersthose a generation or two out of date. If you buy an older adapter, make sure the level of DirectX it supports is high enough to support the games you play.

    Advice from Brian Jepson

    I find the user reviews on NewEgg to be helpful in determining whether a given card might be a hassle under Linux.


  • Make sure that the adapter you choose has drivers available for the operating system you intend to use. This is particularly important if you run Linux or another OS with limited driver support.

The video adapters we recommend are listed at http://www.hardwareguys.com/picks/video.html.

2.1.11. Display

You spend a lot of time looking at your display, so it's worth devoting some time and effort to choosing a good one. The first decision to make when you choose a display is whether to buy a traditional "glass bottle" CRT monitor or a flat-panel LCD display.

WHITHER CRTS?

Our editor comments that CRTs are becoming more difficult to find and the selection more limited, which is true. For that matter, CRT-based televisions are fast waning in popularity. But we believe that CRT monitors will continue to be widely available at least through 2007, and probably into 2008 or later.


Relative to CRTs, LCDs have several advantages. LCDs are brighter than CRTs and have better contrast. Short of direct sunlight impinging on the screen, a good LCD provides excellent images under any lighting conditions. LCDs are much lighter than CRTs, and are only a few inches deep, which makes them more convenient when space is limited. Finally, LCDs consume only 20% to 60% as much power as typical CRTs.

Pay Me Now or Pay Me Later

Their lower power consumption means that an LCD costs less to run than a CRT. The amount you save on your power bill depends on how much you pay for power and how many hours your display is used each day, but saving $25 or more per year is typical for a SOHO system. Over a four- to five-year period, lower power bills may offset the higher initial cost of an LCD display. Against this advantage, however, is the fact that even a high-quality LCD display is unlikely to last as long as a good CRT display.


LCDs also have many drawbacks relative to CRTs. Not all LCDs suffer from all of these flaws. Newer models are less likely than older models to suffer from any particular flaw, and inexpensive models are more likely than premium models to suffer from these flaws, both in number and in degree.

The primary drawback of LCDs is their high price, 50% to 100% more than CRTs of comparable size and quality. (Yes, you can buy a $200 19" LCD, but to match the display quality and durability of a $200 19" CRT LCD you'll have to spend $350 or more on an LCD.) LCDs are optimized for one resolution, usually 1024 x 768 for 15" LCDs and 1280 x 1024 for 17", 18", and 19" LCDs. LCDs backlight the image with an array of cold cathode ray tubes (CCRTs), which are similar to fluorescent tubes and are subject to failure and to gradual dimming over time. An out-of-warranty CCRT failure means you might as well buy a new LCD, because it's very costly to repair.

LCDs have other drawbacks as well. Only fast LCD displaysthose with black-white-black response of 8 ms or lessare acceptable for displaying fast-motion video and games, because on slower models the image smears and ghosts. LCDs have a limited viewing angle. Most graphic artists we've spoken to refuse to use LCDs, because the appearance of colors and the relationship between colors change depending on the viewing angle. LCDs provide less vibrant color than a good CRT monitor. This is particularly evident in the darkest and lightest ranges, where the tones seem to be compressed, which limits subtle gradations between light tones or dark tones that are readily evident on a good CRT. Also, some LCDs add a color cast to what should be neutral light or dark tones. LCDs, particularly inexpensive models, suffer from image persistence, which causes temporary "ghost images."

Finally, some LCDs have one or more defective pixels. ISO Standard 13406-2 defines rules for defective pixels, including their number, type, and locations relative to each other. Defective pixels may be always-on (white, called a Type 1 defective pixel) or always-off (black, called a Type 2 defective pixel). A defective subpixel, called a Type 3 defective pixel, is always on, but displays a color other than white. In general, Type 3 defective pixels are more intrusive visually than Type 1 defective pixels, which in turn are more intrusive than Type 2 defective pixels.

ISO standard 13406-2 defines the four classes of panels listed in Table 2-1.

Table 2-1. ISO Standard 13406-2 panel classes (defects per million pixels)

Class

Type 1

Type 2

Type 3

I

0

0

0

II

2

2

5

III

5

15

50

IV

50

150

500


A Class I panel must be perfectzero dead pixels of any typeregardless of its size or resolution. Such panels are extremely expensive, so nearly all high-quality LCD displays use Class II panels. Some of the very cheapest LCD displays use Class III panels. As far as we know, no one sells a Class IV panel for computer use.

The actual number of defective pixels in a panel of a specific class depends on the resolution of that panel. For example, a 17" LCD display with 1280 x 1024 resolution has 1280 x 1024 = 1,310,720 pixels = 1.31072 million pixels. If the panel is Class II, it can have at most the following number of dead pixels of each type:

Type 1 = 1.31072 x 2 = 2.62144 dead pixels = 2 dead pixels
Type 2 = 1.31072 x 2 = 2.62144 dead pixels = 2 dead pixels
Type 3 = 1.31072 x 5 = 6.5536 dead pixels = 6 dead pixels

So, for example, a 1280 x 1024 panel that had as many as 10 dead pixelstwo Type 1, two Type 2, and six Type 3could qualify as a Class II panel. Defective pixels cannot be "traded" among types. For example, if this panel had three Type 1 defective pixels, it would not qualify as a Class II panel, even if it had zero Type 2 and Type 3 defective pixels. Also, some manufacturers voluntarily exceed ISO 13406-2 requirements. For example, Samsung offers a "Zero Bright Pixel Defect Warranty" on some of its premium models. Although these models use Class II panels, Samsung warrants them to be free of Type 1 defective pixels (although the Class II standards for Type 2 and Type 3 defective pixels remain in effect).

People vary in their reaction to defective pixels. Many people won't even notice a few defective pixels, while others, once they notice a defective pixel, seem to be drawn to that pixel to the exclusion of everything else. Some manufacturer warranties specifically exclude some number of defective pixels, typically between 5 and 10, although the number may vary with display size and, sometimes, with the location of the defective pixels and how closely they are clustered. As long as the display meets those requirements, the manufacturer considers the display to be acceptable. You may or may not find it acceptable.

We formerly suggested that LCDs should be used only if their size, weight, low power consumption, or portability outweighed their higher cost and other disadvantages. Otherwise, we recommended choosing a good CRT and allocating the money saved to other system components. But current LCD displays are better, faster, more reliable, and much less expensive than earlier models. In the 17" and 19" range, a midrange name-brand LCD can cost as little as $100 to $150 more than a comparable CRT, and that differential is soon made up, at least in part, by the LCD's lower power consumption. We currently recommend LCD displays for any mainstream or higher system, and recommend CRTs only for budget systems or for those to whom the color accuracy of CRTs is important.

If you've decided that a CRT monitor is right for you, use the following guidelines to choose one:

  • Remember that a CRT display is a long-term purchase. Even with heavy use, a high-quality CRT can be expected to last five years or more, so buy quality and choose a model that's likely to keep you happy not just for your current system, but for one or even two systems after that.

  • Make sure the CRT is big enough, but not too big. We consider 17" models suitable only for casual use or those on the tightest of budgets. For not much more, you can buy a 19" model that you'll be much happier with. Conversely, make sure your desk or workstation furniture can accommodate the new CRT. Many people have excitedly carried home a new 21" CRT only to find that it literally won't fit where it needs to. Check physical dimensions and weight carefully before you buy. Large CRTs commonly weigh 50 lbs. or more, and some exceed 100 lbs. That said, if you find yourself debating 17" versus 19" or 19" versus 21", go with the larger model. But note that if your decision is between a cheap larger CRT and a high-quality smaller one for about the same price, you may well be happier with the smaller CRT. A $130 17" CRT beats a $130 19" CRT every time.

  • Stick with good name brands and buy a midrange or higher model from within that name brand. That doesn't guarantee that you'll get a good CRT, but it does greatly increase your chances. The CRT market is extremely competitive. If two similar models differ greatly in price, the cheaper one likely has significantly worse specs. If the specs appear similar, the maker of the cheaper model has cut corners somewhere, whether in component quality, construction quality, or warranty policies.

  • If possible, test the exact CRT you plan to buy (not a floor sample) before you buy it. Ask the local store to endorse the manufacturer's warrantythat is, to agree that if the CRT fails you can bring it back to the store for a replacement rather than dealing with the hassles of returning it to the manufacturer. Mass merchandisers like Best Buy usually won't do thisthey try to sell you a service contract instead, which you shouldn't buybut small local computer stores may agree to endorse the manufacturer's warranty. If the CRT has hidden damage from rough handling during shipping, that damage will ordinarily be apparent within a month or two of use, if not immediately.

    Recommended Brands

    Our opinion, which is shared by many, is that NEC-Mitsubishi, Samsung, and ViewSonic make the best CRTs available. Their CRTs, particularly midrange and better models, provide excellent image quality and are quite reliable. You're likely to be happy with a CRT from any of these manufacturers.


  • Most mainstream CRT manufacturers produce threeGood, Better, and Bestmodels in 17", 19", and 21". In general, the Good model from a first-tier maker corresponds roughly in features, specifications, and price to the Better or Best models from lower-tier makers. For casual use, choose a Good model from a first-tier maker, most of which are very good indeed. If you make heavier demands on your CRTsuch as sitting in front of it 8 hours a dayyou may find that the Better model from a first-tier maker is the best choice. The Best models from first-tier makers are usually overkill, although they may be necessary if you use the CRT for CAD/CAM or other demanding tasks. Best models often have generally useless features like extremely high resolutions and unnecessarily high refresh rates at moderate resolutions. It's nice that a Best 17" model can display 1600 x 1200 resolution, for example, but unless you can float on thermals and dive on rabbits from a mile in the air, that resolution is likely to be unusable. Similarly, a 17" CRT that supports 115 MHz refresh rates at 1024 x 768 is nice, but in practical terms offers no real advantage over one that supports 85 or 90 MHz refresh.

  • Choose the specific CRT you buy based on how it looks to you. Comparing specifications helps narrow the list of candidates, but nothing substitutes for actually looking at the image displayed by the CRT.

  • Make sure the CRT has sufficient reserve brightness. CRTs dim as they age, and one of the most common flaws in new CRTs, particularly those from second- and third-tier manufacturers, is inadequate brightness. A CRT that is barely bright enough when new may dim enough to become unusable after a year or two. A new CRT should provide a good image with the brightness set no higher than 50%.

Like all other component manufacturers, CRT makers have come under increasing margin pressures. A few years ago, we felt safe in recommending any CRT from a first-tier maker, because those companies refused to put their names on anything but top-notch products. Alas, first-tier makers have been forced to make manufacturing cost reductions and other compromises to compete with cheap Pacific Rim CRTs.

Accordingly, low-end models from first-tier makers may be of lower quality than they were in the past. The presence of a first-tier maker's name plate still means that CRT is likely to be of higher quality than a similar no-name CRT, but is no longer a guarantee of top quality. Many first-tier CRTs are actually made in the same Pacific Rim plants that also produce no-name junk, but don't read too much into that. First-tier CRTs are still differentiated by component quality and the level of quality control they undergo. There is no question in our minds that the first-tier CRTs are easily worth the 10% to 20% price premium they command relative to lesser brands. In fact, we think it is worth the extra cost to buy not just a first-tier CRT, but a midrange first-tier CRT.

Buy CRTs Locally

After shipping costs, it may actually cost less to buy locally, but that is not the main reason for doing so. Buying locally gives you the opportunity to examine the exact CRT you are buying. Except for LCDs, CRTs vary more between samples than other computer components. Also, CRTs are sometimes damaged in shipping, often without any external evidence on the CRT itself or even the box. Damaged CRTs may arrive DOA, but more often they have been jolted severely enough to cause display problems and perhaps reduced service life, but not complete failure. Buying locally allows you to eliminate a "dud" before you buy it, rather than having to deal with shipping it back to the vendor or manufacturer.


If you've decided that an LCD display is right for you, use the following guidelines to choose one:

  • Current LCDs are available in analog-only, digital-only, and models with both analog and digital inputs. Analog input is acceptable for 15" (1024 x 768) models, but for 17" (1280 x 1024) models analog video noise becomes an issue. At that screen size and resolution, analog noise isn't immediately obvious to most people, but if you use the display for long periods the difference between using a display with a clean digital signal and one with a noisy analog signal will affect you on almost a subconscious level. For a 19" (1280 x 1024) LCD, we regard a digital signal as extremely desirable but not absolutely essential. For a larger display or above 1280 x 1024, we wouldn't consider using analog signaling.

  • Insist on true 24-bit color support, which may be described as support for 16.7 million colors. Most current LCDs support 24-bit color, allocating one full byte to each of the three primary colors, which allows 256 shades of each color and a total of 16.7 million colors to be displayed. Many early LCDs and some inexpensive current models support only six bits per color, for a total of 18-bit color. These models use extrapolation to simulate full 24-bit color support, which results in poor color quality. If an LCD is advertised as "24-bit compatible," that's good reason to look elsewhere. Oddly, many LCDs that do support true 24-bit color don't bother to mention it in their spec sheets, while many that support only 18-bit color trumpet the fact that they are "24-bit compatible."

  • Most LCD makers produce three or more series of LCDs. Entry-level models are often analog-only, even in 19" and 21" sizes, and have slow response times. Midrange models usually accept analog or digital inputs, and generally have response times fast enough for anything except 3D gaming and similarly demanding uses. The best models may be analog/digital hybrids or digital-only, and have very fast response times. Choose an entry-level model only if you are certain that you will never use the display for anything more than word processing, web browsing, and similarly undemanding tasks. If you need a true CRT-replacement display, choose a midrange or higher model with a digital interface and the fastest response time you are willing to pay for.

  • Decide what panel size and resolution is right for you. Keep in mind that when you choose a specific LCD model, you are also effectively choosing the resolution that you will always use on that display.

  • Buy the LCD locally if possible. Whether or not you buy locally, insist on a no-questions-asked return policy. LCDs are more variable than CRT monitors, both in terms of unit-to-unit variation and in terms of usability with a particular graphics adapter. This is particularly important if you are using an analog interface. Some analog LCDs simply don't play nice with some analog graphics adapters. Also, LCDs vary from unit to unit in how many defective pixels they have and where those are located. You might prefer a unit with five defective pixels near the edges and corners rather than a unit with only one or two defective pixels located near the center of the screen.

  • If you buy locally, ask the store to endorse the manufacturer's warrantythat is, to agree that if the LCD fails you can bring it back to the store for a replacement rather than dealing with the hassles of returning the LCD to the maker.

  • If possible, test the exact LCD you plan to buy (not a floor sample) before you buy it. Ideally, in particular if you will use the analog interface, you should test the LCD with your own system, or at least with a system that has a graphics adapter identical to the one you plan to use. We'd go to some extremes to do this, including carrying our desktop system down to the local store. But if that isn't possible for some reason, still insist on seeing the actual LCD you plan to buy running. That way, you can at least determine if there are defective pixels in locations that bother you. Also, use a neutral gray screen with no image to verify that the backlight evenly illuminates the entire screen. Some variation is unavoidable, but one or more corners should not be especially darker than the rest of the display, nor should there be any obvious "hot" spots.

    Recommended Brands

    Our opinion, confirmed by our readers and colleagues, is that NEC-Mitsubishi, Samsung, Sony, and ViewSonic make the best LCDs available. Their LCDs, particular midrange and better models, provide excellent image quality and are quite reliable. You're likely to be happy with an LCD from any of these manufacturers.


  • Stick with good name brands and buy a midrange or higher model from within that name brand. That doesn't guarantee that you'll get a good LCD, but it does greatly increase your chances. The LCD market is extremely competitive. If two similar models differ greatly in price, the cheaper one likely has significantly worse specs. If the specs appear similar, the maker of the cheaper model has cut corners somewhere, whether in component quality, construction quality, or warranty policies.

The CRT monitors and LCD displays we recommend are listed at http://www.hardwareguys.com/picks/displays.html.

2.1.12. Audio Adapter

Audio adapters, also called sound cards, are a dying breed. Nearly all motherboards provide integrated audio that is more than good enough for most people's needs. In particular, the integrated audio provided by nVIDIA and Intel chipsets is excellent, with good support for six-channel audio. Only gamers, those who work professionally with audio, and those who have purchased a motherboard without integrated audio need consider buying a standalone audio adapter.

Use the following guidelines when choosing an audio adapter:


Don't buy too much audio adapter

When you add or replace an audio adapter, don't pay for features you won't use. Don't buy an expensive audio adapter if you'll use it only for playing CDs, casual gaming, VoIP telephony, and so on. Even $25 sound cards include most of the features that more expensive cards provide, and are more than adequate for most purposes.


Don't buy too little audio adapter

If you use your sound card for 3D gaming, buy one with hardware acceleration and other features that support what you use the card for. Capable consumer-grade audio adapters like the M-AUDIO Revolution and Creative Labs Audigy2-series sound cards sell for under $75, and are suitable for anything short of professional audio production.

External USB Sound Adapters

Several companies, including Creative Labs, M-Audio, and Turtle Beach, manufacture external audio adapters that connect to a PC via a USB port. The advantage of these devices is easy installationyou just connect the box to a USB port and install the drivers; no need to open the case. The disadvantage is that you have one more box cluttering up your desk.



Avoid no-name audio adapters

Stick to name-brand audio adapters. We frequently hear horror stories from readers who have purchased house-brand audio adaptersoutdated drivers, missing or inadequate documentation, poor (or no) tech support, shoddy construction, incompatibilities with Windows, and on and on. What's particularly ironic is that you may pay more for a house-brand audio adapter than for a low-end name-brand card. You can buy decent name-brand audio adapters for $25 from reputable companies. Don't buy anything less.

The audio adapters we recommend are listed at http://www.hardwareguys.com/picks/soundcard.html.

2.1.13. Speakers

Computer speakers span the range from $10 pairs of small satellites to $500+ sets of six or seven speakers that are suitable for a home theater system. Personal preference is the most important factor in choosing speakers.

Speakers that render a Bach concerto superbly are often not the best choice for playing a first-person shooter like Unreal Tournament. For that matter, speakers that one person considers perfect for the Bach concerto (or the UT game), another person may consider mediocre at best. For that reason, we strongly suggest that you attempt to listen to speakers before you buy them, particularly if you're buying an expensive set.

Speaker sets are designated by the total number of satellite speakers, followed by a period and a "1" if the set includes a subwoofer (also called a low-frequency emitter or LFE). Speaker sets are available in the following configurations:

  • 2.0: Front left and right satellites

  • 2.1: 2.0 with a subwoofer

  • 4.1: 2.1 with a rear left/right satellite pair added

  • 5.1: 4.1 with a front center-channel speaker added

  • 6.1: 5.1 with a rear center-channel speaker added

  • 7.1: 5.1 with a side left/right satellite pair added

  • 8.1: 7.1 with a rear center-channel speaker added

6.1, 7.1, and 8.1 speaker sets are used primarily by gamers. Some manufacturers have begun to produce "wireless" 5.1 and higher speaker sets. These speaker sets are wireless in the sense that the audio signal is communicated wirelessly; the remote satellite speakers still must be connected to AC power. Wireless speakers use the 2.4 GHz band that is shared with wireless networks, cordless telephones, microwave ovens, and innumerable other devices, so interference is always a consideration. Still, the absence of speaker wires makes it much easier to install these speakers, particularly in a living room, den, home theater, or other residential environment.

The price of a speaker set doesn't necessarily correspond to the number of speakers in the set. For example, there are very inexpensive 5.1 speaker sets available, and some 2.1 sets that cost a bundle. We recommend that you decide on the number of speakers according to your budget. If you have $75 to spend, for example, you're better off buying a good 2.1 speaker set than a cheesy 5.1 set.

The speakers we recommend are listed at http://www.hardwareguys.com/picks/speakers.html.

2.1.14. Keyboards

The best keyboard is a matter of personal preference. A keyboard we really like, you may dislike intensely, and vice versa. Ultimately, your own preferences are the only guide.

Keyboards vary in obvious wayslayout, size, and styleand in subtle ways like key spacing, angle, dishing, travel, pressure required, and tactile feedback. People's sensitivity to these differences varies. Some are keyboard agnostics who can sit down in front of a new keyboard and, regardless of layout or tactile response, be up to speed in a few minutes. Others have strong preferences about layout and feel. If you've never met a keyboard you didn't like, you can disregard these issues and choose a keyboard based on other factors. If love and hate are words you apply to keyboards, use an identical keyboard for at least an hour before you buy one for yourself.

That said, here are several important characteristics to consider when you choose a keyboard:

  • Keyboards are available in two styles, the older straight keyboard and the modern ergonomic style. Some people strongly prefer one or the other. Others don't care. If you've never used an ergonomic keyboard, give one a try before you buy your next keyboard. You may hate iteveryone does at firstbut then again after you use it for an hour or so you may decide you love it.

  • The position of the alphanumeric keys is standard on all keyboards other than those that use the oddball Dvorak layout. What varies, sometimes dramatically, is the placement, size, and shape of other keys, such as shift keys (Shift, Ctrl, and Alt), function keys (which may be across the top, down the left side, or both), and cursor control and numeric keypad keys. If you are used to a particular layout, purchasing a keyboard with a similar layout makes it easier to adapt to the new keyboard.

  • Most current keyboards use the USB interface natively, and are supplied with an adapter for those who need to connect them to a PS/2 keyboard port. We use mostly USB keyboards, but it's a good idea to have at least one PS/2 keyboard available (or a PS/2 adapter) for those times when Windows shoots craps and won't recognize USB devices.

  • Some keyboards provide dedicated and/or programmable function keys to automate such things as firing up your browser or email client or to allow you to define custom macros that can be invoked with a single keystroke. These functions are typically not built into the keyboard itself, but require loading a driver. To take advantage of those functions, make sure a driver is available for the OS you use.

  • The weight of a keyboard can be a significant issue for some people. The lightest keyboard we've seen weighed just over a pound, and the heaviest nearly eight pounds. If your keyboard stays on your desktop, a heavy keyboard is less likely to slide around. Conversely, a heavy keyboard may be uncomfortable if you work with the keyboard in your lap.

  • Some manufacturers produce keyboards with speakers, scanners, and other entirely unrelated functions built in. These functions are often clumsy to use, fragile, and have limited features. If you want speakers or a scanner, buy speakers or a scanner. Don't get a keyboard with them built in.

  • Wireless keyboards are ideal for presentations, TV-based web browsing, or just for working with the keyboard in your lap. Wireless keyboards use a receiver module that connects to a USB port or the PS/2 keyboard port on the PC. The keyboard and receiver communicate using either radio frequency (RF) or infrared (IR). IR keyboards require direct line-of-sight between the keyboard and receiver, while RF keyboards do not. Most IR keyboards and many RF keyboards provide limited rangeas little as five feet or sowhich limits their utility to working around a desk without cables tangling. Any wireless keyboard you buy should use standard AA, AAA, or 9V alkaline or NiMH batteries rather than a proprietary battery pack.

Logitech and Microsoft both produce a wide range of excellent keyboards, one of which is almost certainly right for you. Even their basic models are well built and reliable. The more expensive models add features such as RF or Bluetooth wireless connectivity, programmable function keys, and so on.

The keyboards we recommend are listed at http://www.hardwareguys.com/picks/keyboards.html.

2.1.15. Mice

Choosing a mouse is much like choosing a keyboard. Personal preference is by far the most important consideration. If possible, try a mouse before you buy it.

Small Hands, Big Mouse

Don't assume that hand size and mouse size are necessarily related. For example, Barbara, who has small hands, prefers the Microsoft IntelliMouse Explorer, which is an oversize mouse. She found that using a standard or small mouse for long periods caused her hand to hurt. Changing to a large mouse solved the problem.


Use the following guidelines when choosing a mouse:

  • Mice are available in various sizes and shapes, including small mice intended for children, notebook-sized mice, the formerly standard "Dove bar" size, the mainstream ergonomic mouse, and some oversize mice that have many buttons and extra features. Most people find standard-size mice comfortable to use for short periods, but if you use a mouse for longer periods small differences in size and shape often make a big difference in comfort and usability. Although oversize mice provide attractive features and functions, people with small hands may find such mice too large to use comfortably. Pay particular attention to mouse shape if you are left-handed. Although asymmetric ergonomic mice are often claimed to be equally usable by left- and right-handers, many lefties find them uncomfortable and resort to right-handed mousing. Some manufacturers, including Logitech, produce symmetric ergonomic mice.

  • Get a wheel mouse. Although some applications do not support the wheel, those that do are the ones most people are likely to use a great dealMicrosoft Office, Internet Explorer, Firefox, and so on. Using the wheel greatly improves mouse functionality by reducing the amount of mouse movement needed to navigate web pages and documents. Mice with a tilt-wheel allow you to scroll vertically and horizontally.

  • Standard two-button mice (three, counting the wheel) suffice for most purposes. However, five-button mice are ideally suited to some applications, such as games and web browsing. For example, the two extra buttons can be mapped to the Back and Forward browser icons, eliminating a great deal of extraneous mouse movement.

  • Mice have cords ranging in length from less than 4 feet to about 9 feet. A short mouse cord may be too short to reach the system, particularly if it is on the floor. If you need a longer mouse cord, purchase a PS/2 keyboard or USB extension cable, available in nearly any computer store.

  • Consider buying a cordless mouse. The absence of a cord can make a surprising difference.

  • Buy an optical mouse. Optical mice use a red LED or chip LASER light source and do not require any special mousing surface. Because they are sealed units, optical mice seldom need cleaning. Robert had to take his mechanical mice apart and clean them literally every few days, but his optical mice go for months without cleaning. Fortunately, only the cheapest mice nowadays are mechanical.

Logitech and Microsoft both produce a wide range of excellent optical mice, in corded and cordless models. One of them is almost certainly right for you. Even their basic models are well built and reliable. The more expensive models have more features, are more precise, and are probably more durable. We used Microsoft optical mice almost exclusively for many years, and continue to recommend them. However, when we tested the superb Logitech MX-series optical mice, we found that we preferred their shape and feel. We now use Logitech optical mice on most of our primary systems.

Mouse Alternatives

Consider using a trackball or touchpad, particularly if you experience hand pain when using a mouse.


Avoid cheap, no-name mice. If someone tries to sell you a mechanical "ball" mouse, run.

The mice we recommend are listed at http://www.hardwareguys.com/picks/mice.html.

2.1.16. Network Adapters

A network adapteralso called a LAN (Local Area Network) adapter, or NIC (Network Interface Card)is used to connect a PC to a home or business network. A network adapter provides a relatively fast communication link100 megabits per second (Mb/s) or 1,000 Mb/sbetween the PC and other devices connected to the network. Network adapters are available in wired and wireless versions. A network may use all wired network adapters, all wireless network adapters, or some combination of the two.

2.1.17. Wired network adapters

In a typical wired network, the network adapters in each PC connect to a central hub or switch that allows any connected device to communicate with any other connected device. In a home or SOHO setting, a wired network adapter may also be used to connect an individual PC directly to a cable modem or xDSL modem.

Nearly all wired network adapters support one or more of a family of networking standards that are collectively called Ethernet. Current Ethernet adapters use unshielded twisted pair (UTP) cable, which resembles standard telephone cable, and communicate at 100 Mb/s (100BaseT or "Fast Ethernet") or 1,000 Mb/s (1000BaseT or "Gigabit"). Wired Ethernet adapters use an 8-position, 8-connector (8P8C) jack that resembles an oversized telephone jack, and is usually (although incorrectly) called an "RJ-45" connector.

Many motherboards include integrated wired Ethernet adapters, which are typically 10/100 or 10/100/1000 hybrid devices. You can add wired Ethernet to a system that lacks an integrated NIC by installing an inexpensive PCI expansion card. Integrated network adapters are reliable and add little or nothing to the cost of a motherboard. Standalone desktop PCI network adapters typically cost from $15 to $40, depending on manufacturer and speed. PCI network adapters are often more efficient and fully featured than integrated adapters.

Apples and Oranges

Make sure you know what you're getting when you order a motherboard. Many motherboards are available in several variants, which may provide different levels of integrated Ethernet. For example, the Intel D945GNT motherboard is available in five variants. The D945GNTL and the D945GNTLR provide integrated 10/100 Ethernet. The D945GNTLK, D945GNTLKR, and the LAD945GNTLKR provide integrated 10/100/1000 Ethernet.



Warning: Most Ethernet adapters are backward compatible with slower Ethernet versions. For example, most 100BaseT adapters can also communicate with old 10BaseT devices, and most 1000BaseT adapters can also communicate with 100BaseT and 10BaseT devices. This is not invariably true, however. Some Ethernet devices support only one or two standards. That can cause problems if, for example, you connect a 10BaseT adapter (for example, in an old notebook system) to a hub or switch that supports only 100BaseT or 100BaseT and 1000BaseT. Although the devices can be physically connected, they do not communicate. Components that support multiple speeds, called hybrid components, are usually labeled in the form 10/100BaseT, 100/1000BaseT, or 10/100/1000BaseT.

The best rule of thumb for most desktop systems is to use an integrated network adapter, if your chosen motherboard offers that option and if you do not require the additional management and other features available only with standalone adapters. For servers, use a standalone 100BaseT PCI network adapter, unless you are using a special server motherboard that incorporates one or more server-class 100BaseT or 1000BaseT network adapters. For 1000BaseT on a server, use only an integrated adapter. A PCI 1000BaseT adapter simply consumes too much of the available PCI bandwidth to be usable in such an environment.

If you need wired connectivity, choose a motherboard that provides an integrated 10/100, 100/1000, or 10/100/1000 Ethernet adapter. 10/100 is acceptable for most people's current needs, but Gigabit models provide "future-proofing" at small additional cost.

If your motherboard does not provide an integrated LAN adapter or if you prefer to use a separate LAN adapter, choose one of the wired network adapters we recommend at http://www.hardwareguys.com/picks/lan.html.

Warning

Running at 1,000 Mb/s, a PCI Gigabit Ethernet adapter can swamp the 133 MB/s (1,067 Mb/s) PCI bus, so it's a bad idea to use a PCI Gigabit adapter. Instead, look for a motherboard that provides integrated Gigabit LAN that keeps LAN traffic off the PCI bus by using a dedicated high-speed bus, such as Intel's CSA or Communications Streaming Architecture bus, or a PCIe channel. Alternatively, install a Gigabit Ethernet card that uses the PCIe bus.


2.1.18. Wireless network adapters

Wireless network adaptersalso called WLAN (wireless LAN) cards, 802.11 cards, or Wi-Fi (Wireless Fidelity) cardsuse radio waves to communicate. WLAN adapters communicate with a central device called an access point (AP) or wireless access point (WAP). In a mixed wired/wireless network, the AP connects to the wired network and provides an interface between the wired and wireless portions of the network. One AP can support many WLAN adapters, but all of the adapters must share the bandwidth available on the AP. In a large network, multiple APs may be used to extend the physical reach of the wireless network and to provide additional bandwidth to computers that connect to the network with WLAN adapters.

WLAN adapters are commonly used in notebook computers, either in integrated form or as a PC card. WLAN adapters are also available as PCI expansion cards that can be installed in desktop systems to provide a network link when it is difficult or expensive to run a cable to a system. The original 1997-era WLAN adapters used the 802.11 standard, which supported a maximum data rate of only 2 Mb/s. Those adapters are long obsolete. Current WLAN adapters support one or more of the following standards.


802.11b

802.11b supports a maximum data rate of 11 Mb/s, comparable to 10BaseT Ethernet, and has typical real-world throughput of 5 Mb/s. 802.11b uses the unlicensed 2.4 GHz spectrum, which means it is subject to interference from microwave ovens, cordless phones, and other devices that share the 2.4 GHz spectrum. The popularity of 802.11b is waning because components that use the faster 802.11g standard, described shortly, are now available at low cost, and because most 802.11b components support only the compromised WEP authentication and encryption rather than trustworthy WPA or WPA2. Millions of 802.11b adapters remain in use, primarily as integrated or PC Card adapters in notebook computers.


802.11a

802.11a supports a maximum data rate of 54 Mb/s, and has typical real-world throughput of 25 Mb/s. It uses a portion of the 5 GHz spectrum that until late 2003 was licensed, but is now unlicensed. 5 GHz signals have shorter range and are more easily obstructed than 2.4 GHz signals, but are also less likely to interfere with other nearby devices. 802.11a is incompatible with 802.11b because they use different frequencies. The higher cost for 802.11a devices means they are used almost exclusively in business environments. Most 802.11a components have business-oriented features such as remote manageability that add cost but are of little interest to home users.


802.11g

The most recent WLAN standard is 802.11g, which combines the best features of 802.11a and 802.11b. Like 802.11b, 802.11g works in the unlicensed 2.4 GHz spectrum, which means it has good range but is subject to interference from other 2.4 GHz devices. Because they use the same frequencies, 802.11b WLAN adapters can communicate with 802.11g APs, and vice versa. Like 802.11a, 802.11g supports a maximum data rate of 54 Mb/s, and has typical real-world bandwidth of about 25 Mb/s. That is sufficient to support real-time streaming video, which 802.11b cannot. 802.11g devices now sell for little more than 802.11b devices, so 802.11g has effectively made 802.11b obsolete.


Warning: 802.11b and 802.11g components are standards-based, so devices from different manufacturers should interoperate. In practice, that is largely true, although minor differences in how standards are implemented can cause conflicts. In particular, some high-end 802.11b/802.11g components include proprietary extensions for security and similar purposes. Those components do generally interoperate with components from other vendors, but only on a "least common denominator" basisthat is, using only the standard 802.11 features. The best way to ensure that your wireless network operates with minimal problems is to use WLAN adapters and APs from the same vendor.

"802.108g"

Several manufacturers, including D-Link and NetGear, produce APs that claim to provide 108 Mb/s bandwidth. In fact they do, but only by "cheating" on the 802.11g specification. Such APs, colloquially called "802.108g" devices, work as advertised, but using them may cause conflicts with 802.11g-compliant devices operating in the same vicinity.

802.11g defines 11 channels (13 in Europe), each with 22 MHz of bandwidth. Each 22 MHz channel can support the full 54 Mb/s bandwidth of 802.11g. But these channels overlap, as shown in Figure 2-1. Three of the channels1, 6, and 11are completely nonoverlapping, which means that three 802.11g-compliant APs in the same vicinityone assigned to each of the three nonoverlapping channelscan share the 2.4 GHz spectrum without conflicts. Alternatively, two 802.11g-compliant APs can be assigned to two channels that do not overlap each other, for example, Channels 2 and 8.

Figure 2-1. 802.11g channels

An 802.108g device claims two of the three completely nonoverlapping channels, typically either 1 and 6 or 6 and 11, although it could in theory use 1 and 11. That leaves only one channel available for other 802.11g devices. To make matters worse, although 802.11g APs detect other nearby 802.11g APs and adjust themselves to use nonconflicting channels, many 802.11g APs fail to detect 802.108g APs operating nearby. The 802.11g devices wrongly assume that the channels being used by the 802.108g devices are available, and so may choose to operate on those "available" channels. The upshot is that it's possible, even likely, to end up with an 802.11g device and an 802.108g device attempting to use the same channel at the same time, which means neither device works properly.

If you are building a new wireless network, use a D-Link 802.11g or 802.108g WLAN adapter and AP. Choose 802.11g if channel conflicts are possible, e.g., if you live in an apartment or if your business is in close proximity to other businesses. Choose 802.108g if there are no 802.11b/g APs nearby, but note that you may have to replace 2.4 GHz cordless phones with models that use a different frequency band. If you are expanding a wireless network, use an 802.11g adapter from the same company that made the existing components.

Avoid no-name network adapters and other components. Avoid mixing components from different manufacturers, if possible, particularly in a wireless network. Avoid 802.11a unless you need SNMP remote manageability and other business-oriented features.

Run a Router

If you need to purchase an 802.11g or 802.108g AP, consider buying a model that also incorporates a hardware firewall/router. Using a hardware firewall/router on a home or SOHO network is the single most important thing you can do to improve security and reduce the likelihood that your systems will be infected by a worm.





Building the Perfect PC
Building the Perfect PC, Second Edition
ISBN: 0596526865
EAN: 2147483647
Year: 2006
Pages: 84

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