[New Build]Video Input Suddenly Disappears

Hello,

Recent upgrade on my PC, as follows:

i5-3570K
ASUS P8Z77-V
Corsair TX650W
8GB Patriot 1600Mhz
EVGA GTX660 Ti 3GB
SSD1 Kingston HyperX 120GB
SSD2 OCZ Vertex2 60GB
Seagate 2TB 7200RPM Drive
WD Caviar Black 1TB 7200RPM Drive

All packed into an Antec 300-2. I have a Coolermaster Hyper 212+ cooling the CPU.

The issue, as follows:

PC boots and runs fine. Overclock the GPU to 1215Mhz (mem @ 3500), overclock the CPU to 4.3Ghz and 1.225 Volts. Temps are fine, seemingly and it passes some AIDA64 runs for a few hours on a fresh install of Win7 Ultimate 64bit on the OCZ Vertex2 SSD.

The issue is that I suddenly lose video. In the middle of gaming - or in the case of my wife - online gambling, and it's immediate, the video is gone and my monitor displays No Input. The computer is still running - all LED Fans are running, DVD drive is spinning but no amount of fiddling with the HDMI cable (unplugging, replugging) returns the video.

Proceed to power the PC down. Reseat the video card and plug the power in to the card again. Plug the HDMI cable back into the video card. The interesting thing here is that the HDMI input on the GTX660 is really tight. (Havent tried other inputs, DisplayPort and DVI) I've had to force the cable in to the port or wiggle it around to get it all the way in. Boot the PC and am met with 'Your overclock settings have failed..', etc. Reset again and the PC boots into the OS no problem. Check CPUZ and I'm still overclocked to 4.3.

So.... I'm not sure where to start. My overclock should be fine. The PC seems rock solid. No BSOD's of any kind. I even tuned the OC down to 4.1. Left the voltage where it was. My question to the community is do I RMA video card or are there other things to try first? I have my old GTX460 I could try to see if thats the issue but I have no idea how to reproduce the symptom. It is just random.

Thanks much for any input!

Tim