Dumping physical memory??????????????

ok here is my problem I am playing everquest I have a 64mb video card I bought a 128mb video card off of e-bay when i got the new card i pulled out the old card and when I was about to put the new card in I noticed it was an AGP when I bought and need PCI. So I put the 64 back in and now I am getting an error about five min into the game saying Dumping physical memory. Did I mess up the driver? how do i fix this?

1. You have installed a new hardware device, and this device causes conflict.the solution is removing or disabling that ardware and re-install it again. if the hardware was the main harddisk, then u have no choice but formatting the computer and install the harddisk third pary if it's available.
2. The cash memory or the harddisk have bad sectors or physical damage. in this case re-install the operating system again to make the OS avoid the bad sector.

He hasn't installed any new devices or a new HDD, he has only removed & replaced the same graphics card.

I suggest you make sure that your card is fitted correctly. If it is, try uninstalling then re-installing any drivers.