Computer woes

Well, this is frustrating. My computer has just recently taken to spontaneously shutting down for no apparent reason. No warning or anything, just in the middle of whatever I'm doing ... pfffft. I'm reasonably sure it just needs the power supply replaced, which is about a $100-150 fix.

But it's just over 3 years old and I had been thinking about replacing it this January. Replacing the power supply is a good 10-20% of the cost of a new computer. The idea of being without a computer for a protracted period strikes fear into my heart, so it seems reasonable to replace it early.

I haven't bought a computer in three years, so I've fallen behind in what's good, what's not, and what former players in the market are a shadow of themselves. I'm thinking about either going with a mail-order configurator like Cyberpower, but I've also considered getting a premade system at Circuit City or Best Buy and dropping in a decent graphics card. I'm avoiding Dell. I think their quality has improved over what it once was, but I think they're overpriced. Does anyone have any suggestions as to a vendor or experiences they'd like to share?

And just to stave off the inevitable, no a Mac is not an option.

UPDATE: No boot for me! It looks like the turning-off-unexpectedly problem has turned into a wont-even-boot problem. Nuts. Thank goodness for work laptops you can take home. Posting may be light for the next couple of weeks. Fortunately, I don't think I lost any data. Since this is probably a power supply problem, it should all be intact on the hard drive. When I get a new computer, I'll get an external drive encloser and drop my old hard drive into that. That way I'll have all my old data and a backup drive, too!

Hey, if you do mostly desktop applications, word processing, email and the like, a Mac is probably a good choice. On the other hand, you can get a decent PC suitable for doing all those things for a third of the price. Wow, it looks like you can even get an ultra-portable from Dell for $350. Admittedly that's probably not good for much other than web browsing and email, but damn, you can spend more than that on a PDA.