I just recently replaced my GTX 275 SLI setup with a single 680. Everything worked fine for a couple of days but then my computer stopped booting up. Instead of the normal beep that verifies POST I got 1 Long beep and 2 short ones. I looked up the code and it appears that it could be a display issue. The odd thing is that I've figured out if I unplug my computer, switch the PSU to the off position, and hold down the power switch to recycle the power, when I plug everything back in and power on, the computer starts normally with no problems. Once the computer is on, there seem to be no other issues. It also should be noted that I am able to reboot the computer successfully and the issue only occurs after a full shutdown. I am at my wits end, and trying to decide if I need to RMA my GPU or if its power related so I would appreciate any help.
Motherboard: MSI X58m
CPU: Intel Core i7 920 @ 2.67 GHz
GPU: Nvidia GeForce GTX 680
Power Supply: Antec True Power 850W
OS: Windows 8 Professional
Memory: 6144MB RAM