Defining the Portable Computer
| Portables, like their desktop counterparts, have evolved a great deal since the days when the word portable could refer to a desktop-sized system with a handle on it. Today, much smaller portable systems can rival the performance of their desktop counterparts in nearly every way. Many portables are now being marketed as "desktop replacements," which are portable systems powerful enough to serve as a primary system. This chapter examines the phenomenon of portable computing, showing how it has evolved and why it is so popular. Portables started out as suitcase-sized systems that differed from desktops mainly in that all the components, including a CRT-style monitor, were installed into a single case. In the early 1980s, a small Houston-based startup company named Compaq was among the first to market portable PCs such as these. Although their size, weight, and appearance are almost laughable when compared to today's laptop or notebook systems, they were cutting-edge technology for the time. In fact, unlike modern laptops, the components used by these bulky first generation portables were virtually identical to those used in the most powerful desktops of the day. Most current portable systems are now approximately the size of the paper-based notebook they are often named for and are built using the clamshell design that has become an industry standard. Inside these systems, nearly every component has been developed specifically for use in mobile systems. Portable PCs, however, are not the same as Personal Digital Assistants (PDAs), such as the Palm series, Handspring, and PocketPC. Portable computers differ from PDAs in that they use the same operating systems and application software as desktop computers and use memory, CPU, and drive technologies that are similar to desktop PCs as well. PDAs, on the other hand, use different operating systems, applications, and hardware compared to either desktop or portable PCs and thus fall outside the scope of this book. Instead, this book focuses primarily on laptops or notebook-style portable PCs. That said, in terms of technology, much of this book will also be applicable to a relatively new category of portables: Tablet PCs. Actually Tablet PCs have been around since the early '90s, but a lack of standardized software, combined with relatively low power and functionality, limited them to special applications rather than mainstream use. In many respects, modern Tablet PCs are identical to laptop/notebook computers except that they are equipped with a touch-sensitive display, lack the integrated removable storage (such as a CD/DVD-ROM drive), and include a special tablet-oriented version of Windows. While most include a keyboard and basically look like a standard notebook computer, a few Tablet PCs do not come with a keyboard at all. Those that don't include a keyboard generally offer one as an accessory or can use any standard external keyboard if desired. Many people use portable systems as an adjunct or accessory to a primary desktop system in their principal working location. In those cases, the portable system may not need to have all the power of a desktop, since it will only be used when away from the main office. In my situation, the roles are reversed. All my professional life I have been teaching PC hardware and software, usually on the road. As such I have always needed a powerful computer I can take with me, and because the amount of time spent traveling is equal to or more than the amount of time spent at a home office, I have had to rely on portable PCs of one type or another as my primary system. All my books on upgrading and repairing PCs, starting with my first self-published seminar workbooks in 1985, have been written on a portable system of one type or another. With the processing power of modern laptop/notebook systems evolving to the point where they are nearly equal to all but the most powerful desktop systems, I look forward to carrying even smaller, lighter, and more powerful laptops in the future. Portable computers have settled into a number of distinct roles that now determine the size and capabilities of the systems available. Traveling users have specific requirements of portable computers, and the added weight and expense incurred by additional features make it less likely for a user to carry a system more powerful than is necessary. Others may not do much traveling, but simply like the flexibility and small footprint that a laptop provides. Portable System Design ElementsObviously, portable systems are designed to be smaller and lighter than desktops, and much of the development work that has been done on desktop components has certainly contributed to this end. Much of this development has been in simple miniaturization. For example, whereas 3.5-inch hard drives may be popular on desktops, most laptops would not have room for these devices. Instead, they normally use 2.5-inch hard drives, which are a direct result of the miniaturization that has occurred in hard-drive technology over the past few years. Some of the subnotebook and Tablet PC systems use even smaller 1.8-inch drives first made popular in portable music players. In addition to miniaturization, however, advancements in three other areas have contributed greatly to the design of today's laptop computers: flat-panel displays, power systems, and thermal management. Flat-Panel DisplaysThe sleek lines of flat-panel Liquid Crystal displays (LCDs) have caused them to be seen increasingly more often on desktops. It was not long ago, however, that these displays were almost exclusively in the domain of laptops. A flat-panel display is one of the most visually apparent components of a laptop. They are also usually the component that has the greatest impact on the size, shape, and cost of a laptop. In the early days of portables, the only affordable portable display was the small CRT monitor, a device that was so power-hungry that it required AC power. These displays were also bulky, causing early portables to look like small suitcases. When gas-plasma displays became available, the size of portables diminished to that of a lunchbox or briefcase. Still, the power requirements of gas-plasma displays again mandated a nearby AC outlet. It was not until the development of large, low-power LCDs that the familiar clamshell-style, battery-powered laptop became a reality. As the internal components of a laptop became increasingly small, the laptops gradually shrunk in size to the point where they were no larger than a paper notebook. Indeed, the category of notebook computers originally started out with a footprint no larger than 8.5x11 inches. In the past few years, however, as high-quality LCD screens became available in larger and larger sizes, the size of some notebooks also increased. Low Power ConsumptionLike the car that spends most of its time in a garage, or the pleasure boat that spends most of its time at the dock, portable computers spend most of their time in a decidedly non-mobile environmenton a desk connected to an AC power outlet. Take away a laptop's battery, however, and you have greatly diminished its value. In fact, one of the primary features of importance to a laptop buyer is the "battery life"the length of time the system can run on a single battery charge. Environmental concerns are leading to the development of more efficient power-management technologies, but, obviously, operating a computer from a battery imposes system limitations that designers of desktop systems never had to consider before the advent of battery-powered portable systems. What's more, the demand for additional features, such as DVD and CD-RW drives, larger displays, and ever faster processors, has enormously increased the power drain on the typical system. The problem of conserving power and increasing the system's battery life is typically addressed in three ways:
Thermal ManagementPerhaps a more serious problem than battery life in portable systems is heat. All electrical components generate heat, of course, and in the confines of a laptop this heat can be a significant problem. Inside a laptop, a large number of components are packed in a relatively small space, creating an extremely high concentration of thermal energy. This energy must somehow be dissipated. In most desktop systems, this is accomplished by using fans that continuously ventilate the empty spaces inside the system. Because fans use up battery power, however, portable systems must be designed to run fan-free most of the time and therefore employ innovative systems for moving and dissipating heat. The worst culprit, as far as heat is concerned, is the system processor. When they were first released, the amount of heat generated by Intel's 486 and Pentium processors became a problem even in desktop systems. Newer and faster processors consume more and more power. It became clear to processor manufacturers such as Intel and AMD that special processor designs would be necessary to reduce power consumption and thermal output in mobile systems. Modern mobile processors benefit from technology featuring lower voltages, smaller die sizes, larger integrated caches, and, in general, lower power consumption than their predecessors. Because many portable systems are now being designed as replacements for desktops, they require the most powerful processors available. Even the newest and fastest processors designed for desktop systems are often adapted for use in mobile systems. Even with dedicated designs for mobile systems, these high-speed processors can generate surprisingly large quantities of heat. To address this problem, Intel and AMD have created special methods for packaging mobile processors that are designed to keep heat output to a minimum. Mobile processors also reduce heat through the use of extra-low-voltage designs (multiple voltages in recent designs) and by integrating both the Level 1 and Level 2 memory cache directly on the processor die. These techniques, by the way, not only reduce heat but also lower power demands and thus increase battery endurance. However, even the best mobile processor designs will still result in a substantial quantity of heat being generated in a small space. Usually this heat is more concentrated than that inside a desktop. To cope with this problem, many notebook components are designed not only to require little space and power but also to be able to withstand high temperatures. The Popularity of PortablesOffice staffers frequently have to take work home. Salespeople regularly crisscross the country, spending more time in their cars than at their desks. Construction engineers need computing power, but rarely sit inside a traditional office. It is no wonder that portable computers have had an almost continuous presence in the computer industry. In fact, not only do portable computers comprise a significant portion of total annual computer sales, that portion is continually growing, and is even exceeding that of desktop systems in some cases. For example, according to the research firm Current Analysis, laptops outsold desktop systems for the first time in the U.S. during the calendar month of May, 2005, accounting for 53 percent of the total market during that month, up from 46 percent during the same period in the previous year. As further evidence of the popularity of laptops, Intel said that about 31 percent of its processors will end up in mobile computers in 2005, compared with only 17 percent in 1999. IBM reported in 2000 that they sold a total of 10 million ThinkPad laptops in the 8 years since their first appearance on the market in 1992. They doubled that figure to 20 million total ThinkPad laptops by 2003, only 3 years later. Not only are laptops growing in popularity as compared to desktops, but the total market for laptops has been increasing as well. According to DisplaySearch Inc., laptop sales for 2004 were expected to exceed 46 million units, an astonishing figure when you look at it. Finally, according to Charles Smulders, vice president and chief analyst at Gartner Dataquest, "…the mobile segment has represented one of the few areas of sustained growth in an otherwise difficult PC market. Between 1998 and mid-2002, mobile PCs increased their unit share of the global PC market by over 50 percent. For every four PCs shipped, one is now a mobile, and this share is projected to rise further, approaching one in three by 2006." Who's Selling Laptops?Because of their popularity, laptop and notebook computers are available from a large number of vendors. Table 1.1 lists the major laptop/notebook vendors in the U.S., along with the brand names associated with those vendors.
Although there are many vendors of laptops, most vendors do not manufacture these devices themselves. In fact, 65% of all laptops are produced in Taiwan by one of several companies located there. These companies are not well known because the systems they manufacture are usually not labeled with their own name, but instead are privately labeled with the name of the vendor. Here's a list of the major manufacturers in Taiwan; while most of them sell systems under other names, a few of these companies also sell systems under their own labels as well:
An increasing portion of notebooks is being produced in mainland China as well. The largest builder of notebooks in that country is Lenovo, who acquired IBM's Personal Computing Division (global desktop and notebook PC business) in 2005. This acquisition makes Lenovo/IBM the third-largest global PC leader, behind Dell and HP/Compaq. |
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