Siobhan's computer killed another video card, after only a few months more than a year. So it's time to look at both a short-term and a long-term solution.
The real limitation is that we've got an AGP slot. Long ago we poured a lot of money into a high-end video card that used AGP, the best video slot available at the time. It lasted for years, but it was a massive heat-producer and power-hog, and we'd put it into a fairly low-end computer, the kind that's more than adequate for word processing and browsing the web and watching videos, but nowhere near up to the challenge of high-end gaming challenges. But with this video card (which cost as much as the computer, back then) it was able to handle The Sims, which I didn't really realize at the time was a high-end gaming challenge, in terms of its video and CPU load.
The video card died at a time when we didn't have a ton of money lying around, so we looked to replace it. Since we had an AGP slot, we looked for AGP cards. The prices had dropped substantially, so we got a card that promised to be as powerful as the one it was replacing, and then some, but which cost a fraction as much, produced less heat, and consumed less power. All good things. But when we got it, the system didn't work very long before it crapped out on us again.
Testing revealed the video card was good, but all the strain and heat had screwed up the rest of the system too. So now we had a brand new AGP video card and needed to replace the motherboard, and still didn't have a lot of money. After several attempts to replace parts of the system, we ended up replacing the case, the power supply, the motherboard, the CPU, and the RAM. Over the course of a couple of months, we replaced everything except the hard drive, CD-ROM drive, and some of the internal cables. A real unity of the organism question.
The result was a good case with great ventilation, an overpowered power supply, but a motherboard that was still pretty low-end -- far better than what it replaced, but for its time, still not exactly a gaming system. More importantly, hampered in our choices by still being committed to AGP, which by then was almost totally out of use, as it is now.
I hate to replace this video card with another AGP, and continue to propogate this AGP thing indefinitely, with fewer and fewer choices that cost more and more every time. So the new plan is to spend the minimum possible for a used-but-working AGP card that's only intended to last a few months, then to replace the motherboard and the video card. This time it won't be the cheapest one that does the job. It'll be one picked to handle The Sims 2, which is clearly as demanding as anything out there. If possible, it'll use our existing dual-core CPU and the RAM we already have, though if it can't, that's okay. But we'll use the same case, drives, and power supply for sure.
Once again it'll be a new computer but with the same hard drive and OS so we can once again dodge Windows Vista. Exciting!