I have a Dell Optiplex, and the onboard video died.  I cannot get into the bios, to tell it to let me use a video card, because I cannot get any video at all.  Can anyone help me figure out a fix?Most PC's...(newer) will recognise when a vid card is added and AUTOMATICALLY DISABLE onboard...Thank you for your help, but this system does not work that way.  I have hooked monitors up to it, that I know work, because they are working on other SYSTEMS.  And it will not recognize them.What about it tells you it is just the video output?

Does the machine still boot into windows/can you log in?

Or do you get nothing at all?The MOTHER board lights up, and you can even hear the system post and boot.  However, there is absolutely nothing on the MONITOR screen.  The power light is on, but there is nothing on the screen, it is completely black.I would say that if the Dell cannot recognise and use an external video card, and you are quite sure the onboard video is kaput, then effectively the motherboard is dead. Thank you for your help!