Upgrading a PC

Sometimes it’s sensible to upgrade a PC. Other times, it’s not. Whether it is economically feasible to upgrade a particular PC depends largely on how old the PC is, its existing configuration, and what you expect it to do.

PCs less than a year or two old are usually easy to upgrade. Components are readily available and sell at market prices. Necessary BIOS upgrades and firmware revisions are easy to obtain. PCs more than two or three years old are harder and more expensive to upgrade. Necessary components, particularly memory and BIOS upgrades, may be difficult or impossible to obtain. Even if you can obtain them, they may be unreasonably expensive. Upgrading one item often uncovers a serious bottleneck elsewhere, and so on. In general, restrict older PCs—say anything older than a Pentium III or late-model Celeron system—to minor upgrades such as adding memory or replacing a hard disk. Although you can do significant upgrades on older systems, it seldom makes economic sense to do so. If an older PC requires more than minor upgrades to meet your expected needs for the next year or so, it’s probably not a good upgrade candidate.

The reason most people upgrade their PCs is to improve performance. The good news is that there are several relatively inexpensive upgrades that may yield noticeable performance increases. The bad news is that some are easier than others, and that doing all of them can easily cost as much or more than simply buying a new PC.


Upgrading the processor improves overall system performance. In general, upgrade only within the same generation, for example, a Pentium II/266 to a Celeron/500, or a Pentium 133 to a K6-2/400. Avoid upgrade kits that jump generations, e.g., kits to upgrade a 486 to Pentium, or a Pentium to Pentium II. These kits are usually expensive, provide limited performance improvements, and are often plagued with compatibility problems. If you upgrade within the same generation, you may have to upgrade your BIOS at the same time (usually a free download), and you may have to buy an adapter (for example, to install a Socket 370 Celeron in an older Slot 1 motherboard). In general, newer systems are easy to upgrade, and older systems are more difficult (or impossible) to upgrade. Upgrading processors is covered in Chapter 4. Cost: $30 to $200 (although you can spend much more). Difficulty: Easy to difficult, depending on the system and the processor.

L2 cache

Modern processors (Pentium II/III/4, Celeron, Athlon, Duron) have L2 cache built into the processor package. Old Socket 7 processors (Pentium, K6/K6-2) depend on discrete L2 cache that resides on the motherboard. On such systems, particularly if little or no L2 cache is already installed, adding L2 cache may provide a 10% to 25% boost in overall system performance. Upgrading L2 cache is covered in Chapter 3 and Chapter 5. Cost: $25 to $50. Difficulty: Easy to moderate, depending on the type of L2 cache the motherboard accepts. Note, however, that fifth-generation systems with discrete L2 cache are now so old that it seldom makes sense to spend even $25 upgrading them.


If your PC does not have at least 64 MB (Windows 95/98/Me), 128 MB (NT/2000), or 256 MB (XP) of RAM, adding RAM is the most cost-effective upgrade you can make. Additional memory improves overall system performance, sometimes dramatically. Adding memory beyond 96 MB for 95/98/Me, 128 MB for NT/2000, or 256 MB for XP results in decreasing returns. The downsides are that many older systems do not cache memory above 64 MB (check the motherboard/chipset manual), which means that increasing memory beyond 64 MB can actually decrease performance, and that you may be sinking money into an obsolete form of memory that cannot be migrated later to a new system. Upgrading memory is covered in Chapter 5. Cost: $25 to $150 (varies with memory size and price). Difficulty: Usually easy, although physical access on some older systems is difficult, and the correct memory may be hard to find and expensive.


If you use your CD-ROM drive only for installing software and listening to music, even an original 1X model suffices. But if you use your CD-ROM drive for playing games, accessing large databases, or ripping audio CDs to MP3 format, you’ll want a better drive. Recent 32X and faster IDE models are inexpensive and easy to install. However, rather than installing a new CD-ROM drive, consider installing a CD writer and/or a DVD-ROM drive. Upgrading CD-ROM drives is covered in Chapter 10. Cost: $50. Difficulty: Easy.

Hard disk

Modern hard disks are huge, fast, and inexpensive. Upgrading the hard disk not only provides additional storage space, but can dramatically increase performance if you run applications that access the disk frequently. Older systems cannot recognize large hard disks, but that problem can be gotten around by using a device driver (usually included with the new drive), by installing a BIOS upgrade, or by replacing the embedded IDE interface with an expansion card ($25 to $50) that supports large drives. Upgrading hard disks is covered in Chapter 13 and Chapter 14. Cost: $75 to $250. Difficulty: Easy, except for problems migrating existing programs and data.

Video adapter

Video adapter technology improves almost from month to month. Even so, if you use your system primarily for word processing, email, web browsing, and similar functions, you won’t get much benefit from upgrading to a new video adapter. But if you play 3D games and your video card is more than a year or so old, upgrading to a more recent model can provide dramatic performance benefits. Although it seldom makes sense to install the latest, fastest video adapter in an older system, installing a mid-range current video card can boost performance at small cost. Upgrading video adapters is covered in Chapter 15. Cost: $50 to $200. Difficulty: Easy to moderate.


Although CRT monitors are a mature technology, manufacturing improvements and other factors have resulted in dramatic price reductions on larger models. Not long ago, 15” monitors were the norm and 17” monitors sold for $750. Nowadays, decent 17” monitors cost $150 and 19” monitors $300. If you spend a lot of time in front of your PC, buying a bigger monitor may be the best upgrade you can make. Also, unlike most upgrades, a good monitor is a long-term asset. You can use it with your current system, your next system, and probably the next system after that. Upgrading monitors is covered in Chapter 16. Cost: $150 to $700. Difficulty: Easy.

Power supply

Although it may seem strange to include power supplies in the performance upgrade category, the fact is that many systems have inadequate power supplies, and replacing the original unit with a better unit can improve system performance and stability. Upgrading power supplies is covered in Chapter 26. Cost: typically $45 to $125. Difficulty: Easy.

Another reason to upgrade a PC is to add missing features. Here are some common feature upgrades:

CD writer

A CD writer allows you to burn your own CDs, which can subsequently be read in any recent CD-ROM drive. CD writers are popular for making archival backups and, of course, are used by many people to make pirated copies of data and audio CDs. Adding a CD writer is covered in Chapter 11. Cost: $100 to $250. Difficulty: Easy for IDE drives, easy to moderate for SCSI drives.

DVD-ROM drive or DVD writer

A DVD-ROM drive allows you to watch DVD movies on your PC and to access the increasing number of databases and games supplied on DVD. DVD-ROM drives can also read data and audio CDs, so they are becoming a popular replacement for CD-ROM drives. DVD writers are to DVD-ROM drives as CD writers are to CD-ROM drives. In addition to playing back video, audio, or data DVD-ROM discs, a DVD writer can write large amounts of data to a removable disc or cartridge that costs $3 to $40. Adding a DVD-ROM drive or DVD writer is covered in Chapter 12. Cost: $85 to $250 (DVD-ROM) or $450 to $750 (DVD writer). Difficulty: Easy for IDE drives, easy to moderate for SCSI drives.

Tape drive

The downside of huge, cheap modern hard disks is that there is no practical means to back them up short of installing a tape drive. Tape drives store huge amounts of data—up to 50 GB or more—on relatively inexpensive tape cartridges. Adding a tape drive is covered in Chapter 9. Cost: $200 to $900. Difficulty: Easy for IDE drives, easy to moderate for SCSI drives.

Sound card and speakers

If you make no serious demands on the audio capabilities of your PC, the inexpensive sound card and speakers that probably came with it are usable. But PC audio hardware and applications are advancing faster than any component except video adapters, and there are a lot of fascinating new applications, including 3D gaming with positional audio, DVD playback, IP telephony, voice-recognition software, and so on. To use any of these new applications, you may need to replace your sound card and perhaps your speakers. Adding a sound card and speakers is covered in Chapter 17 and Chapter 18. Cost: $50 to $400. Difficulty: Easy, except for potential conflicts with improperly uninstalled drivers from the original sound card.

Game controller

Years ago, people bemoaned the fact that PC games were not up to the standards of arcade games or dedicated game machines like those from Sega, Sony, and others. Dramatic improvements in PC video and audio mean that nowadays the situation is exactly reversed. The best games run on PCs, the Sony PlayStation series and Microsoft X-Box notwithstanding. But getting the most from those games requires adding dedicated game controller hardware. Adding a game controller is covered in Chapter 21. Cost: $10 to $150. Difficulty: Easy.

The ultimate upgrade, of course, is to replace the motherboard, which in effect means building an entirely new PC. Before you undertake a motherboard upgrade, consider whether you might not do better to retire your current PC to other duties and buy or build a new system. If you do replace the motherboard, expect to pay $85 to $250 for the motherboard itself, but also plan to spend another $50 to $1,000 to replace processor, memory, and perhaps other components, depending on how much can be salvaged from the current system. Difficulty: Easy to moderate (although it may be time-consuming) if you have some experience working on PCs. Moderate to difficult if you don’t.

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