Video card troubles?

I plugged in a video card into the pci slot and everything worked fine, except everytime I did those periodic updates from microsoft and norton, it wouldn't work, the computer would boot, but the moniter would say no signal, I would change the slot the card was in, and reboot than it would work fine, however, the last time I did this, it didn't fix the problem, I never disabled the onboard video card (option not in bias and cannot locate the jumper) but now nither card will "awaken" a monitor so that I can at least see the computer boot, not the old card nor the new one. (I used the new one to S-Video to my TV) any help please? atleast get me able to see my pc again...|||When you go into the BIOS and tick the onboard video and change it to disable, it should ask you to hit F10. That will save the choice to the CMOS and you should have no issues. But if that doesn't do it and you need to use jumpers, go to the mother board maker's site or what ever company made the machine and get the pic (should be in a PDF file).|||The video card may not be plugged in properly or there may be a short somewhere. From http://fixit.in