ACCORDING TO the U.S. Census Bureau, there are 25,150 "places" in the United States, and that means I need a new computer.

This is not a non sequitur, just a statement of fact. The thought occurred to me while I was staring at the screen of the PC in my basement, watching Microsoft Excel display an hourglass while it determined where each of those 25,150 locales - from Adak, Alaska to Yoder, Wyoming - ranks in terms of median family income.

I watched that hourglass for what seemed like an eternity before Excel figured everything out. So, when I decided to rank the same 25,150 places by housing values, I figured I'd time the process - 5 minutes and 15 seconds. Since I had a lot of rankings to go, I knew it would be a lousy way to spend a weekend.

Sometimes this goes with the job. When I'm not writing a column and editing our technology section, I'm in charge of crunching numbers for the newsroom. Every 10 years, after the government counts us and asks us how much we earn and how many toilets we own, it dumps truckloads of numbers on us. We're supposed to make sense of them - and these days we have to do it on a deadline.

For this we can thank the quantum leap in computing power that has arrived on our desktops since the 1990 census.

I've had this particular computer for a couple of years now - it's a slapped-together, no-name with a 600 MHz Athlon processor - and recently I've had a hankering to move on to something better.

Unfortunately, until now, I'd never run across anything I wanted to do that this machine wouldn't handle with reasonable aplomb - including editing digital photos, compressing MP3 music files and grinding through some pretty large databases. That made it hard to justify spending the dough on a new toy.

This is a problem for the entire PC industry. Most of us use our computers to write letters and reports, surf the Web, send e-mail, chat online and look after our finances. None of these chores has put any strain on a PC for years.

In fact, when my older son graduated from college, got a job and replaced his old computer with a slick new Pentium 4, he got bored with it after a couple of days. "It's not like I actually need all this," he said.

If you want to know why computer makers are pushing digital video so hard in their ads, it's because video editing is one of the few jobs that actually needs a souped-up processor. Otherwise, most computer users don't have any real reason to upgrade.

Well, I have a reason now, thanks to the Census Bureau. The question is how much power I need.

When I got back to the office on Monday, the machine I use at work every day ripped through the same calculations in just over two minutes, less than half the time it took my clunker at home. This isn't surprising, since the office machine, an 18-month-old Dell Pentium III with a 1 GHz processor, runs almost twice as fast, and it's made from better components.

So what could I expect from a really quick PC? Back home, I loaded the spreadsheet on my son's new computer, a slick 1.8 GHz Dell. The result: one minute and 55 seconds, only a few seconds better than the PC at the office - a machine with a processor that's a generation behind and half as fast.

Now this is hardly a scientific benchmark test, but it's a reasonable one. It measures applied computing power in its most elemental form - spreadsheet calculations don't depend on disk drives, fancy video circuits and other such goodies.

Other than hardware, the main difference between my work PC and my son's monster is that I'm running Windows 98 and he's using Windows XP, Microsoft's latest and greatest operating system. It's accepted that XP is a bit slower than its predecessor, but should an operating system suck up 90 percent of the extra processing power you pay for in a state-of-the art computer?

I think that's exactly what's happening. When I finally persuade my wife that I need a new PC, it will burn me up that I'm burning up half that new computing power just to stand still.

eMac vs. iMac?

Speaking of new computers, Apple has quietly introduced the iMac that many of its users really wanted in the first place - only it's called an eMac.

The "e" stands for education, the market Apple originally targeted with the new machine, an enlarged version of its original, one-piece iMac with a 17-inch cathode ray screen. The screen has a 40 percent larger viewing area than the original iMac's 15-inch tube, which was always too small for a lot of adult eyes.

The schools have long been a key market for Apple, but one that has succumbed to successful attacks in recent years from Dell and other Visigoths of the Wintel empire who peddled cheaper machines.

When it introduced the slick new iMac earlier this year - with its swiveling, 15-inch liquid crystal display - Apple scored a hit with its home and professional users. But a big chunk of its $1,400 price tag was accounted for by the flat panel monitor - which made it too pricey for the perennially cash-strapped education market.

So Apple introduced the eMac strictly for schools with an $1,100 entry-level price tag. Lo and behold, regular customers liked the new machine, too. With a 700 MHz G4 processor, it was just as powerful as the new iMac, and it had a larger screen to boot. True, it took up more desk space and didn't look as cool, but for a lot of us, cooler isn't always better.

So now Apple's offering the eMac to everyone. If you're a Mac fan - particularly if want a good starter machine for your parents - it's a good buy.