I have an Optiplex 780 and it worked fine until video card went...I tried to install a modified GT430 but it was a full card. I unplugged and removed the VGA outlet and modified it with a low profile backing plate into a low profile card. I installed the card in the computer but all i get is like sleep mode on the monitor but the computer boots up. I tried resetting defaults in bios, clearing bios, re-seating the video card but nothing seems to work. i take out the card and it boots up fine. The video works as i tried it in another computer...will it not work because it's not really a low profile card? i did it before with another computer and it worked so not sure if it's just the dell system or maybe the PCI-E slot is kaput?