Have you tried different cables and a different monitor with any of the other cards?
Given that you've tried PCI, PCIe and onboard, I'd be suspecting the mobo, but trying a different cable and monitor will prove it. At that point you will have isolated everything.
Every search I do for your mobo gives me a G31 board, which, with all due respect, is one of the worst board on the market (IMHO). I installed a few for customers who requested them, but they always had problems within the first 12 months.