A naughty, misbehaving GeForce 4 MX 4000...

Righto. I used to have me a Pentium III 667, 256mb SDRAM, and a GeForce 4 MX 4000 in my PC. Just the other day, I decided to buy myself a P4 1.6ghz with a GeForce 2. "Hey, I can just put my GeForce 4 in! It'll be great! No problems!" Or so I thought. But I was also hoping my incredible bad luck with computers was going to leave me alone.

So, here's the problem. I put my GF4 into my new PC. No picture. In fact, the computer makes the same responses (read: beeps) with the GF4 in as when there isn't any video card in at all. Note that I was playing KotOR the day before on the old PC, so it was fine.

I tried to put the GF4 back in the old PC. Now it wasn't working there, either. In fact, an S3 Savage 2000, a GF2 and the GF4 all don't work in the old PC anymore. And of those three cards, only the GF2 works in the new PC.

What's going on? Why did all my cards magickly stop working? And why does the slot on my old PC seem to be dead?

The Old:
Windows XP Pro
PIII 667mhz
GeForce 4 MX4000 128mb
256mb SDRAM
40gig HDD

The New:
Windows XP Pro
P4 1.6ghz
GeForce 2 MX/MX400
512mb SDRAM
Motherboard: IBM 6792 22A