DVI not working

I put my PC on standby the other night and when I tried to continue my game the next day the monitor would not come on. Thought my 8800gt had died but when I put my 7600gt in the same problem.

I can get the monitor to work with the analog on board video but when I connect the DVI on either card the monitor goes into safe power mode.

As I started the second paragraph the thought came to mind that it might be the DVI cable, I don't know.

 

Turn off both PC & LCD. Unplug both power cords for 5 mins. Plug 'em back in. Hook up DVI cable from pc to LCD. Turn on PC. Wait 1 min. Turn on LCD.

 

Actually, unplugged for over thirty minutes travel to and from Best Buy thinking the gpu was bad. The tech there suggested leaving PC for diagnostics, but I wanted to swap in my other gpu. Well, I got good advice on this forum that solved another issue so I thought I'd look to you guys before I tried anything else.