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Solve : use PCMCIA card in DOS? |
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Answer» I have an "elderly" notebook computer that does not have a built-in ethernet port. I'm using a TrendNet cardbus PCMCIA card instead. Works fine in Windows, but I'm trying to get it to load in DOS, with no luck so far. Not even lights on the card. I'm not sure but I don't think PCMCIA cards/drivers will work in a PC-Card slot- one would need PC-Card Bus drivers, and I doubt those are available for MS-DOS. Alright, now I'm more confused. You gave me tips on how to do this, but now say you don't think it can be done? PCMCIA cards/drivers and PC-Card cards/drivers are one and the same: PCMCIA is the association that defines standards for PC-Cards/slots. This must be able to work...you started saying you had an elderly laptop which now turns out to be a newer model. the newer models use PC-card. PC-Card can use PCMCIA cards. However- a PC-card bus needs a driver. a PCMCIA driver probably won't work. and DOS-based PC-card drivers likely don't exist for that particular laptop, if at all. they aren't the same; although my use of terms wasn't quite accurate. Major Features No matter which type of laptop you have, you can be sure that it has a somewhat standard set of components. Later in this book we will discuss these components in more detail. Processors There has always been a range of processors available for laptops, but one rule has almost always applied: The fastest laptop is almost never as fast as the fastest desktop. The problem is one of power. Fast desktop processors run on AC power, of which there is a relatively limitless supply available. Portables in most cases at least occasionally must run on batteries, which have to be small enough so that the laptop can be lifted. Portable systems are also smaller than most desktops, and the tighter confines mean that the ability to run a high heat-producing processor is more limited. Therefore, a mobile processor in general has a more limited amount of electrical power available. Intel has responded to the needs of mobile systems by offering low-power "M" versions of its most popular processors. Figure 2.1 shows the Pentium 4-M chip, the mobile version of the Pentium 4. These processors are generally similar to the desktop versions except they use lower voltages internally and can adjust their clock speeds depending on the user's requirements. By lowering their voltages and clock speeds, these chips can cut their power requirements and thus extend a notebook's battery endurance. Note also that the maximum clock speeds of these chips are almost always slower than those of desktop chips. Figure 2.1. The Pentium 4 Processor-M chip from Intel. (Photo courtesy of www.intel.com.) Table 2.3 shows a comparison of the clock speeds of various mobile processors from Intel. Table 2.3. Clock Speeds (in GHz) Available for Intel's Mobile Processor Chips Intel Mobile Processor Clock Speeds (GHz) Pentium M 1.0 to 2.26 Mobile Pentium 4 1.4 to 3.46 Celeron M 0.8 to 1.5 Mobile Celeron 0.65 to 2.8 In March of 2003, Intel introduced its Pentium M chip for laptops, a part of its Centrino platform. The Celeron M followed as a low-cost version of the Pentium M. Unlike previous mobile processors from Intel, these chips are not a variation on a desktop chip, but a Pentium-compatible processor built from the ground up for mobile applications. Intel claims that laptop designers can achieve 1040% longer battery endurance if they use this chip. In addition to the chips' energy conservation, Intel also claims that the Pentium M and Celeron M are faster than they may appear. Because they use a different internal architecture, they are able to squeeze out more effective work during each clock CYCLE. As a result, you cannot directly compare the clock speeds of Pentium M/Celeron M and other mobile Pentium chips. For example, Intel claims that a typical laptop running a 1.6GHz Pentium M chip will race through benchmark programs 15% faster than a Pentium 4-M running at 2.4GHz. Intel also claims that this same laptop's batteries last 78% longer on the Pentium M than on the Pentium 4-M. Another processor specifically designed for portable applications is the Efficeon chip from Transmeta. This chip promises very low power consumption but at the expense of processing speed. The Efficeon has a different instruction set than Intel Pentium processors, requiring it to perform extra steps to translate the Pentium instructions into a form that the Efficeon can understand. Thus, although the Efficeon may have clock speeds comparable to Pentium M chips, its performance is considerably slower. Unfortunately, Transmeta has yet to capture much of the market and is concentrating more on licensing its power-saving technology rather than selling processors. Some laptop manufacturers occasionally opt for the highest performance possible by using desktop processors. As can be expected, these power-hungry chips result in surprisingly short battery endurance. Note, however, that this quest for desktop performance is never completely successful. Overall system performance depends not merely on the processor but on several other components, and as a result these devices have yet to equal the performance of the fastest desktops. You can find more information on mobile processors in Chapter 4. Video Display Size and Resolution Ever since the days of the luggables in the early 1980s, the design of portable computers has been highly dependent on the latest lightweight displays. When low-power LCDs became available, the development of the battery-powered laptop finally became possible. Today, the size of the display is the single most important determinant of the size of the laptop. Currently, virtually all laptops use active-matrix color displays. These screens provide needle-sharp images of high contrast, in most cases better than the CRT displays that most desktops use. Indeed, many desktop users are now upgrading to flat panels. The prime impetus for this switch may be to save space, but the improved image quality is at least a partial factor. There are, however, a few drawbacks to LCD displays. The first is that they have a fixed or native resolution. CRT displays can easily switch to higher or lower resolutions. When LCDs are moved above or below their native resolution, however, the image becomes decidedly blurry or even distorted. The second drawback of LCDs is their limited field of view. These displays may present high-quality images, but only to viewers sitting directly in front of the screen. People who may be sitting a few feet to the right or left of that optimal position may see an image where the colors have been shifted and the contrast lowered. With the increasing popularity of LCD televisions, some LCD manufacturers are developing screens that are more suitable for wide-angle viewing. If you plan to use your laptop for informal presentations, you should take a look at laptops that advertise wide-angle capability. Of course, some people prefer a more limited viewing angle because it makes it harder for other people to read your screen when you are working in public. One other downside of LCD screens is that they are considerably more expensive than CRTs. The good news here, however, is that the prices of LCDs have continually dropped over the years and will continue to do so. Indeed, the popularity of desktop LCD displays should lead to increased volumes and lower prices for both desktops and laptops. Because the technologies used in today's LCDs are basically similar, the main differences among screens have to do with their sizes, their resolutions, and their aspect ratios. Chapter 11, "Graphics and Sound," includes more detailed information on displays. Screen Size Size is, of course, the most visually apparent property of an LCD screen. In general, as time progressed, screens became continually larger. There is, however, a size limit for laptops. As LCD screen sizes moved beyond 17 inches, measured diagonally, they became too large to be portable and were relegated to desktop use. In today's laptops, screen sizes vary from 7.2 inches (measured diagonally) for the smallest systems to 17 inches for the largest. The most common size is now 14.1 inches, which represents a good compromise between size and portability. In general, users are well advised to get the largest screen they can comfortably carry and afford. But note that for some screen sizes, there may be a choice of several different resolutions available. Choosing the wrong resolution may make the screen harder to read, or limit the amount of information that can be displayed. Screen Resolution The resolution of a screen depends somewhat on its size. As the size of the screen increases, it can comfortably accommodate more pixels, thus allowing for increased resolution. For 14.1-inch screensthe most common varietymost laptop manufacturers offer two choices of resolution: XGA and SXGA+. A few vendors also offer SXGA, but the unique aspect ratio (5:4) makes that size and resolution somewhat rare. The increased resolution of SXGA+ over standard XGA enables users to display nearly 87% more onscreen information such as folders, documents, web pages, and so on, at the same time. Increased resolution also increases pixel density (the number of pixels per inch of screen size), which in turn increases the apparent sharpness of photographs and graphic images. Some people even maintain that increased pixel density increases the readability of text. On the downside, however, increased resolution also decreases the size of standard text and icons on the screen. As personal preference varies, users should personally examine several different size/resolution combinations to see which seems best to them. Note that once you have chosen a resolution, it cannot be changed. A laptop's video circuitry can simulate a change in resolution, but the resulting image will be much less sharp than the image at the screen's original or native resolution. Table 2.4 lists common LCD screen sizes and the resolution they support. Table 2.4. Screen Size and Resolution: A Sampling of the Most Common Combinations Available for Laptops Screen Size (in.) Resolution Type Resolution Aspect Ratio Pixel Density (Pixels/in.) 12.1 SVGA 800x600 4:3 83 12.1 XGA 1024x768 4:3 106 13.3 XGA 1024x768 4:3 96 14.1 XGA 1024x768 4:3 91 14.1 SXGA 1280x1024 5:4 116 14.1 SXGA+ 1400x1050 4:3 124 15.0 XGA 1024x768 4:3 85 15.0 WXGA 1280x800 8:5 101 15.0 SXGA+ 1400x1050 4:3 117 15.0 UXGA 1600x1200 4:3 133 15.4 WXGA 1280x800 8:5 98 15.4 SXGA 1280x1024 4:3 106 15.4 WSXGA+ 1680x1050 8:5 129 15.4 WUXGA 1920x1200 8:5 147 17.0 WXGA+ 1440x900 8:5 100 17.0 UXGA 1600x1200 4:3 118 17.0 WUXGA 1920x1200 8:5 133 Screen Aspect Ratio The aspect ratio for most laptop displays is the same as that for desktops and televisions: 4:3 (that is, the height of the screen is 3/4 the width). In the distant past, some laptops, such as the IBM PC Convertible and the Toshiba T1000, used wider display screens because that was all that was available. When 4:3 LCD screens came out, the public quickly gravitated toward this standard shape. Now, however, with the popularity of DVDs and high-definition TV, many manufacturers are installing widescreen displays on their systems (see Figure 2.2). These displays have a wider aspect ratio of 8:5 (16:10). Note that although this is much wider than the standard computer display, it is not quite as wide as the 16:9 proportions of HDTV, but is able to accommodate a full 16:9 HDTV picture within a 16:10 display with only a small upper and/or lower border (often used by the DVD player controls). Widescreen laptops are usually sold as multimedia or desktop replacement systems, due to their larger (and clumsier to carry) sizes. As more people use their laptops in home entertainment systems or as personal DVD players, expect this number to grow. Figure 2.2. The Dell Inspiron XPS Gen 2, with its 17-inch WUXGA display. (Photo courtesy of Dell Inc.) [View full size image] One interesting thing to note is that having a widescreen display doesn't necessarily mean you get more resolution or desktop screen real estate. For example, many so-called "widescreen" laptops have 15.4-inch WXGA (1280x800) displays. Personally, I would rather have a standard aspect ratio 15.1-inch SXGA+ (1400x1050) display because even though it doesn't have the "widescreen" aspect ratio, it actually offers an overall wider and deeper image in pixels than the so-called widescreen display. At the higher 1400x1050 pixel resolution, you'll actually be able to fit more open windows (web pages, applications, and so on) both in width and depth than you could on a WXGA screen. In fact, the SXGA+ screen has nearly 44% more overall resolution, MEANING you can fit that much more content on the screen. The primary advantage of using a widescreen on a laptop is that human vision sees more peripherally than vertically, making wider screens better suited to what you actually see on them. Video Accelerators A crucial and sometimes overlooked aspect of computer performance is the speed of its video accelerator. This chip, shown in Figure 2.3, speeds up the process of moving pixels around the screen. Computer game players have been especially sensitive to the speed of their video processors because this can greatly influence the quality of their entertainment. But business users should also be aware that a video accelerator can impact tasks such as sales presentations. Figure 2.3. Video accelerator chips from NVIDIA. (Photo courtesy of www.nvidia.com.) Currently, the best laptop video accelerators are from ATI and NVIDIA. Note that as in the case of processors, laptop video accelerators are usually not quite as fast as those in desktop models. Typical video accelerators are listed in Table 2.5. Table 2.5. Typical Video Components and the Best Optical Drives Available for Different Laptop Types Laptop Type Screen Size (in.) Video Accelerator Video Memory (MB) Optical Drive Desktop replacement 15.4/17 ATI Radeon X300/X600 NVIDIA GeForce Go 6800 128/256 DVD/CD-RW or DVD+/-RW Mainstream 14.1/15 Intel Media Accelerator 900 ATI Radeon 9000 ATI Radeon X300/X600 64/128 DVD/CD-RW or DVD+/-RW Value 14.1/15 Intel Media Accelerator 900 64/128 DVD/CD-RW Thin & light 14.1 Intel Media Accelerator 900 ATI Radeon X300/X600 64/128 DVD/CD-RW Ultralight 12.1 Intel Media Accelerator 900 64/128 None In addition to the type of video accelerator used, laptop users should also pay attention to the amount of video memory installed. The amount of video memory used for laptop graphics chipsets currently varies from 64MB to 256MB. In most cases the video memory is dedicated memory (separate from main RAM) used to hold information that will eventually be displayed on the screen. However, systems with video accelerators built into the motherboard chipset (such as the Intel Media Accelerator 900) use shared memory, which means that the video accelerator borrows main system RAM for video use. Since there is no dedicated video RAM, this results in a less expensive design (which also uses less power), but sacrifices performance when compared to dedicated video memory designs. The more video memory available, the more colors the laptop can display and the faster the video accelerator can operate. Large amounts of video memory are also useful for 3D graphics such as in games. Purchasers should be CAREFUL to note the type of video chipset and amount of video memory in a potential new notebook. Although there are a few select models with upgradeable graphics, in most cases the video accelerator components cannot be changed. You'll find more detail about mobile video chipsets in Chapter 11. Spindles (Storage) The classic three-spindle laptop is disappearing. These systems generally had three forms of rotating memory: a hard drive, an optical drive, and a floppy drive. Now, because floppy disks are so rarely used, many laptop manufacturers have been leaving them off in order to save weight and lower costs. In some two-spindle systems, the floppy can be swapped into the storage bay normally occupied by the optical drive, but you can't run both simultaneously. In most cases, the floppy is relegated to being used as an external device that connects to the system via a USB cable. Since floppy drives aren't used much anymore, this doesn't seem to bother many people, which is one reason the three-spindle designs are fading. As average file sizes continue to grow well past the capacity of a floppy, this once familiar component may well disappear altogether. Currently, most vendors offer external USB floppy drives for laptops as a $50 option. The most important drive in a laptop is its hard drive. Currently, drive sizes range from 20 to 160GB. Many experts suggest that users get as much hard drive storage space as they can afford. When users eventually purchase a digital camera or start storing audio and video on their hard drives, they will soon take advantage of all the storage space they have available. External USB drives can also be used to extend the storage of a laptop, and are actually quite excellent for backup, but when mobile, you generally have to rely on the drive that is installed internally in the system. Some laptops have drives that rotate at higher speeds than other drives. The use of faster rotating drives will positively impact system performance by a significant amount. A faster-spinning drive enables the system to access information from the hard drive more quickly. Faster drives also have a major impact on startup (boot) times, as well as the time it takes to hibernate and resume from hibernation. For some time there has been a variety of optical drives available for laptops. Most systems today include either a DVD-ROM drive, a combo DVD/CD-RW burner, or a DVD+/-RW drive, many of which can also handle DVD-RAM as well. In most cases these drives are not nearly as fast as their desktop counterparts, especially where DVD burning is concerned. In most cases if you plan on doing any significant DVD burning, I recommend attaching an external USB desktop DVD burner. Chapters 9, "Hard Disk Storage," and 10, "Removable Storage," discuss storage options in more detail. Expansion Options Laptop components are so tightly crammed together that few expansion options are available. Often the only way to expand the capabilities of a laptop is to insert a PCMCIA (Personal Computer Memory Card International Association) card (see Figure 2.4). These cards, also known as PC Cards or CardBus Cards, were originally designed as memory cards but are now capable of providing a wealth of features. Almost any feature not provided on a laptop or not provided in sufficient quantity can be added via a PCMCIA card. Figure 2.4. A diagram of the PCMCIA PC Card. Note that there are two types of PCMCIA cards and three sizes. In addition to the older 16-bit PC Card, there is also a high-speed 32-bit CardBus Card that is required for high-speed wireless networking cards. The three sizes are Type I, Type II, and Type III, which mainly vary in thickness. "Cardbus" is likely the bus used by the expansion slots on any motherboard newer then about 2000; Although its possible the Cardbus interface itself will run via a 16-bit DOS PCMCIA driver, I highly doubt that and am fairly sure that even in that unlikely case that the use of the bus will be limited to 16-bit cards, of which network cards are not- netowrk cards are built to the 32-bit Cardbus standard. The fact that drivers for MS-DOS are not available for newer technology is not particularly surprising. |
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