No matter what computer you buy today, you'll always have second thoughts about it.

"If I'd only waited a couple of months," you'll say, "I could have gotten a lot more for a lot less money."

And you'll be right -- there's always a better deal just around the corner. So, when I make my semiannual "what-PC-to-buy" recommendations as the summer and winter solstices approach, I try to balance price, performance and longevity.

The current state of affairs illustrates Moore's Law, named after Gordon Moore, a founder of the Intel Corp. Years ago he predicted that the power of microprocessors would double about every 18 months, leading to a spiral of better computers for less money.

Moore turned out to be a pessimist. Thanks to competition and manufacturing efficiencies in monitors, printers, hard drives and other components that aren't strictly chip-related, the price of computing horsepower has dropped even faster than he predicted.

For example, when I bought my current computer 18 months ago, the 300 MHz Pentium II system was close to the top of the line. Today, you can't find a machine that slow on the market -- the closest models are in the sub-$1,000 range. And you know what? My computer is still a solid workhorse -- good enough so that the hassle of setting up a new one and moving all my software and files isn't worth any gain I'd get in performance.

So, if you're buying a PC today, take heart. Sure, you're buying into obsolescence. But it costs a lot less than it did before, and if you buy wisely, your computer will last quite a while.

Now for the nitty-gritty. I've always recommended that you buy the best technology you can afford, but that doesn't mean you have to throw away perfectly good money. While you can buy a usable PC with a monitor for as little as $600 or spend $3,000 for a high-end game and graphics blaster, you can get an excellent system that will handle most household, office, entertainment and educational chores for well under $1,500.

By that I mean a PC that will handle word processing, spreadsheets, financial software and Web browsing effortlessly (none of these seriously taxes a decent machine) and leave you with enough punch for fun stuff -- games, photo editing and music. It doesn't matter which brand you buy (although you'll want at minimum a one-year warranty with service in or near your home). The important thing is to make sure the PC has the proper components. Here's a checklist:

Microprocessor: This is the heart of your computer -- the faster and more capable the processor, the better it will perform. The good news is that choosing a processor is tougher than ever. Intel markets three distinct versions of its Pentium chip -- the Pentium II, Pentium II and Celeron, while rival AMD offers three models of its K6 processor. You'll also find a variety of low-end computers using Cyrix processors.

For general home and office use, you'll find excellent buys in PCs with Intel's newer Celeron processors (400 MHz or faster). The original Celeron was a dog, but the latest designs are far more efficient and include an on-board memory cache that comes close to matching Pentium II performance. PCs using AMD's K6-2 chips with similar speed ratings offer similar speed.

Memory: If you have a choice between a slightly faster processor and more internal memory, go for the memory. It will make your machine faster -- particularly if you like to run several programs at once -- and you'll be less prone to crashes. At a minimum, get 64 megabytes of RAM; 128 megs is even better. Some otherwise excellent low-end machines ship with only 32 megs of RAM; if you buy one, have the dealer upgrade the PC to 64 megs before you leave the store -- it should add no more than $75 to the bill.

Hard drive: Games, graphics and bloated application programs chew up more hard disk space than they did a few years ago, but for once, hardware makers are ahead of the curve with massive drives at mini-prices. Look for a computer with at least 6 gigabytes of hard disk space. Any drive larger than 9 megs is overkill -- unless you're editing high-resolution photographs or want to store feature-length movies on your disk.

Video: This is another area where low-end PC makers cheap it out. Look for a video adapter with 3D hardware acceleration and at least 8 megabytes of on-board memory. If you're a serious gamer, you may want to upgrade upgrade to a video card designed specifically for game play and graphics.

Monitor: Most decent PCs are sold with 17-inch monitors today, but sub-$1,000 systems often substitute cheap 14- or 15-inch screens. Bigger monitors are much easier on the eye. If you want a real treat, try one of the new 19-inch models. One major exception: Dorm rooms are crowded and desks are often Lilliputian. If you're buying a computer for a college student, a 15-inch monitor may be more comfortable.

Look for a monitor with a dot pitch (the distance between pixels on the screen) of .28mm or less. Make sure it displays bright, crisp text, with lines that are straight from edge to edge and colors that don't fade or bleed from one area of the screen to another. Also look for controls that correct problems with the size, shape and placement of the image, including pin-cushioning and barrel distortion.

CD-ROM: Unless you're an inveterate game player or want to watch full-length movies on your PC, the CD-ROM drive that comes as standard equipment will do just fine. If you're interested in cutting-edge entertainment or movies, spend another $100 to $200 for a higher-capacity DVD (Digital Versatile Disk). It will give you access to the latest DVD games as well as to DVD movies, which are increasingly popular in video stores.

Sound: The sound card packaged with most PCs is adequate for home and small business use. If you're looking for maximum 3D performance with games and music, find a PC with the new Sound Blaster Live! from Creative Labs. True Sound Blaster hardware (as opposed to emulations) is also a good idea if you want to use speech recognition software.