15.2 Choosing a Video Adapter Use the following guidelines when choosing a video adapter: Remember that video is just one part of your system. If your system has only a Pentium II/233 and 32 MB of memory, you're likely to be disappointed if you install a cutting-edge $400 graphics card. Buying a $150 midrange graphics card instead and spending the other $250 on a CPU, motherboard, and memory upgrade yields much better video performance, and increases general system performance as well. Unless you spend most of your computing time running resource-intensive 3D games, performance is probably the least important selection criterion. All current video adapters, and many older models, are more than fast enough to run standard 2D business applications at normal resolutions and refresh rates (e.g., 1024 x 768 at 85 Hz). Previous-generation 3D adapters are discounted deeply when their replacements ship, and are excellent choices for most users. These older video chipsets are often used for embedded video on integrated motherboards, and will suffice for nearly anyone. Don't forget that today's obsolescent chipset was the leading-edge barn burner not long ago. Don't get caught up in the horsepower race, and don't waste money buying performance that you'll never use. Choose the correct interface. If you have an AGP slot, buy an AGP adapter. An existing AGP motherboard may have a 1X, 2X, or 4X AGP slot. Most current AGP adapters are 4X, but some 2X models remain on the market. The increased throughput of AGP 4X is likely to remain largely unused for some years, but AGP 4X adapters are ubiquitous and are ordinarily the best choice, even if your AGP slot does not support 4X, because 4X cards are generally of a later design and offer better graphics performance. With some limitations, any AGP adapter of the proper voltage can be used in any AGP slot, although performance will be limited by the slot or the adapter, whichever is slower. All recent mainstream operating systems support AGP, except Windows NT 4, which treats AGP video cards as PCI devices. The best course is simply to make sure that any motherboard you buy provides a 4X AGP slot and that any AGP card you buy supports AGP 4X.  | Some AGP motherboards have mechanical or electrical limitations that prevent them from accepting some AGP cards. Conversely, some AGP cards cannot be installed or do not function properly in some AGP motherboards. These problems were caused both by ambiguities in the AGP standard and by some manufacturers failing to adhere closely enough to the published standard. These problems were relatively common with motherboards and video adapters designed and sold in the late 1990s through about late 2000, and in particular with motherboards that use a VIA chipset. No current motherboards or AGP cards that we know of suffer these incompatibilities. If you're working with old components, check the maker's web site for details about possible conflicts. |
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If you have no AGP slot, buy a PCI adapter. PCI adapters are still available, although selection is becoming increasingly limited. You may have to settle for a graphics chipset that is two or three generations out of date, because recent chipsets are often available only on AGP cards. Still, if the video adapter in your system is more than a year old, installing even an inexpensive current model PCI video adapter can provide dramatic improvement for 3D applications. If you have only ISA or VLB slots, your system or motherboard is too old to be economically upgradable. Display quality is subjective and very difficult to quantify, but a real issue nonetheless. The consensus, with which we agree, is that Matrox video adapters provide the highest 2D display quality. Many other adapters provide reasonable 2D quality, but the fastest 3D adapters sometimes compromise 2D quality. Buy a high-end 3D accelerator only if 3D graphics are your primary consideration. Before you purchase a motherboard with embedded video, verify that the embedded adapter can be disabled, allowing you to replace the adapter in a year or two, when even inexpensive adapters will greatly outperform your embedded adapter. If possible, choose a motherboard that has an available 4X AGP slot. The availability of PCI adapters is waning, and you may have few or no choices in PCI video adapters by the time you're ready to upgrade. Buy a card with enough memory. PCI video cards can use only memory that resides on the card itself. AGP video cards can also use main system memory, but for performance and other reasons it's always better to have the necessary memory on the video card itself. For a video card used primarily for business software and other 2D applications, 4 MB is marginally adequate, allowing up to 1600 x 1200 resolution at 64K colors. You're better off with 8 MB or more, which is enough to run 32-bit color at up to 1280 x 1024 adequate for all but 20" and larger monitors. Note that 16 MB adapters often sell for little more than 8 MB ones, and that additional 8 MB is useful for caching fonts and other graphics elements. If you run hardware-intensive games like Quake 3, consider 16 MB the absolute minimum. Some low-end consumer-oriented 3D accelerators still ship with only 8 MB, which is adequate for running 3D at 800 x 600 resolution. Running 32-bit color at 1024 x 768, however, requires nearly 8 MB just to store the x-, y-, and z-buffers, leaving no memory available on an 8 MB adapter for storing textures and other elements. Although AGP adapters can use main system memory as video memory, for performance reasons most gamers prefer to have a large amount of video memory physically installed on the video card. If that's the case for you, buy an AGP card with at least 32 MB of DDR-SDRAM memory, and 64 MB is better. 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 Windows NT/2000/XP, Linux, or another OS with limited driver support. The best vendors, like Matrox, provide frequent driver updates. Matrox offers better driver support than any manufacturer we know of. They provide three levels of driver: Microsoft-certified (slowest, but stable), Matrox-certified (faster, but not certified by Microsoft), and beta (fastest, but not certified by anyone). Some video card manufacturers (we won't name names to avoid being sued) focus most of their driver development resources on Windows 9X, and provide only primitive, low-performance, feature-poor drivers for less popular operating systems. Consider the manufacturer's history of providing frequent driver updates and supporting new operating system versions, which you can determine by examining the manufacturer's web site, checking the Usenet newsgroups, and cruising the hardware enthusiast web sites. Make sure the video card has a good warranty. Video cards used to be among the most reliable components of a PC. This is changing, not because manufacturers are cutting corners, but because new high-performance video cards are pushing hardware technology to the limit. Having a video card die after only six months or a year is now relatively common, particularly for those who push the card past its limit by overclocking it in pursuit of the highest possible performance. We've seen video cards with 90-day warranties, which is completely unacceptable. Regard one year as an absolute minimum, and five years is better. |
