1) Replace parts in my computer to bring it up to previous spec.
Cost: $300. No, I'm not joking. Dual-CPU mobos aren't cheap, and neither are high-end PSUs.
Pros: I'd have my computer working fully again.
Cons: My computer kind of sucks at this point, and while it would, in fact, be working 100%, 100% on this computer really isn't all that impressive anymore. Plus that's $350 for a kind of sucky computer.
2) Replace parts in my computer to get it working (single CPU, less excellent PSU).
Pros: I'd have a working computer until I upgrade. Also, I can probably get the parts at Fry's.
Cons: It would be an even more sucky computer. I'd also have a spare CPU sitting around. What do you do with a lone CPU? (Answer: build an extremely cheap computer around it and use it as a gateway?)
3) Replace the mobo with a single-CPU mobo and buy it a top-end PSU.
Pros: I'd have a working computer until I upgrade, and wouldn't be wasting money on a lousy PSU.
Cons: If I misjudged which PSU to buy, I'd just end up with a very expensive spare. Also, I'd need a buy another PSU anyway if I wanted this computer to still be functional.
4) Buy an entire new computer.
Pros: New computer, top-end.
Cons: Pricey. Plus, some of the hardware and software I really want doesn't quite exist yet, though it's damn close.
I think I'm leaning towards #2. It's not really that pricey, and it's hard to have too *many* moderately-good computers lying around. Also, my strategy of "never rely on onboard components" means that I really don't care what the cheap motherboard has on it, as long as it can drive a single Athlon CPU at reasonably high speeds - and let's be honest, that's not even reasonably high speeds today.
Dammit, this means I'm going back to single-CPU hell.
And I'll be downgrading just in time for Halflife II.