I've gone into device manager and can't see the card in there (i'm looking under the system devices tab. However something interesting... the VIA CPU to AGP controller is showing as a problem device with the following:
"This device cannot find enough free resources that it can use. (Code 12)
If you want to use this device, you will need to disable one of the other devices on this system.
Click Troubleshoot to start the troubleshooter for this device."
Not sure if thats got something to do with the issue?
Oh god, my friend had this problem - I fixed it for him, by updating his BIOS. Try that