I recently upgraded to a ZOTAC AMP! GTX 660 Ti but I've encountered a frustrating issue: after the computer sleeps and I wake it up, I don't get a display signal over HDMI (I even get the Windows chime when a device is disconnected). I didn't have this problem with my old card (560 Ti 448). I've tried reinstalling drivers, made sure my PSU was adequate (650w), and double checked that there aren't any monitor driver updates I'm missing (Asus doesn't provide drivers for my monitor apparently). I thought the card was defective, so I successfully RMA'd, but the new replacement card is doing the same dang thing. I figured that the odds I got two defective cards were slim, so I tried a spare DVI cable and THAT works. I can get HDMI to come back if I unplug my computer for 5~10 min, but DVI seems to always work (typing right now). I'm stumped. Anyone else run into this?
Edit: The problem has been solved, it was a bad HDMI cable. Thanks again everyone.