More often than I expect, I get mail that boils down to something like this: "I have a ten-year-old 386 PC with 16MB of RAM running Windows 3.0. How can I upgrade it to work with today's software and hardware?" The short, snotty answer: Use it as a stand for a new machine.

In the DOS days, it was different. By the time my original IBM PC was seven years old, it was the King of Upgrades. I had swapped out the original text-only video board in favor of one that could do monochrome graphics. An amazing 20MB hard-drive card whirred in a neighboring slot. Beside it stood a multifunction card that boosted the original 64KB of memory tenfold and added a serial port for the outboard modem. I'd even performed a PC brain transplant: In the socket where the poky 8088 processor originally resided sat a connector cabled to a blazingly fast 80286 on its own card. The machine may have had an IBM logo on it, but when I was through with it, the thing was virtually a Stephen Manes autograph model.

Back then, internal upgrades made sense. Today, in a world of dizzying deflation for every part in the box (aside from monopoly-priced software), they generally don't, except to stave off the horrible experience of reinstalling your data and programs on a new machine. My advice: Avoid that, and the upgrades themselves, by buying more machine than you think you need. (And yes, I'm well aware that a sizable chunk of this issue of PC World is devoted to an upgrade guide.)

Start with enough memory in the box, and you'll avoid the hassle of figuring out which stick of add-in RAM you need and of deciphering the baffling diagrams that purport to show you how to install it. Buy enough storage in the first place, and you won't have to worry about the goofy errors that inevitably arise from full disks or fiddle with cables, screws, and software to install a second drive (assuming there's room for it). Get a read-only optical drive-CD-ROM or DVD-ROM--plus another that's recordable, and you'll be able to copy disks from one to the other with relative ease. Demand a network interface, and you won't need to install one later or mess with USB-to-ethernet kludges. And if you buy a PC with extra bays and slots, you can still upgrade if you must.

Few upgrades--especially processor add-ins--deliver enough speed to justify their cost. Hard drives don't add much performance, either. True, if you're woefully short of RAM--say, under 256MB--adding more should make things zippier. But otherwise, performance is basically limited by what you buy at the outset.

Hard-disk space is different: More is more. But unless you're a video or music junkie, you may well need a new PC before you fill up one of today's big drives.

So which upgrades still pay off? External peripherals often do. Monitor prices have dropped so much that unless you own an iMac you no longer have any excuse for enduring a dinky, second-rate 15-inch screen. Printers keep improving, too, particularly for color photos. Modern dirt-cheap scanners often beat ancient expensive models.

The most useful upgrades add functionality. Today, the most important of all involve connectivity, such as fast cable or DSL hookups and ways to network your machines (with or without wires) so they can share in the upgrade from dial-up. And if you've already got the hottest PC on the block but still have an urge to upgrade, there's always one long-lasting improvement that can be the most consistently satisfying of all: a new chair.

PC World Contributing Editor Stephen Manes was a cohost of Digital Duo, a public television series. He has been writing about PCs for nearly two decades.

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