I just got a used dell dhs desktop, and would like to add a PCI video card to it. Installed the card, and the drivers, and when i did that, i lost video signal on the original video card, and also on the new video card. When remove the new video card, the computer boots up and defaults back to the stock video card. can this computer handle the video card? it's a ATI R9000 dual monitor card. Thanks!