My second hand AGP inno3D 6800GT is painfully slow. I get 2200 on 3dmark05 and 28000ish on Aquamark 3 whereas most with similar specs get 5000 and 60000. The card appears fine. I have stopped every process but the essentials. Ihave colbits with 400/1.1 overclock, but unlocking the 81.98 drivers made no difference.
That is very strange for a Geforce 6800GT. Looking at your system specs, your hardware isn't the problem.
The main problem seems to be your IRQs. If you have anything plugged into your USB ports while using your video card, there are going to be some problems. Try re-assigning the IRQs manually, either through Device Manager or the BIOS, take your pick.
That would also explain why futuremark is picking this thing up as pci.
But for one last thing - check your BIOS and make sure that the 6800GT is set as the primary graphics adapter. It should say AGP - not PCI.
Hopefully one of those will fix your problems :wink: