It's been happening for a while now but during most games, (not all, just most) of Game of Thrones LCG my entire computer will lock-up. I can see my mouse cursor move and my friend reports that he can see me move cards around when I try to click the screen. If I open task-manager, my entire screen simply goes back and I am forced to reset my entire computer. Surprisingly, I am still able to switch to a different account while the account that has OCTGN open is completely black. I usually use Skype during games but it's happened on other programs as well such as Google+ chat.
Windows 7 64-bit w/ SP1 Ultimate
8 GB Corsair RAM sticks (4GB each)
Intel i5-3570K CPU
Sapphire Radeon HD 7850
This never happens when I run any other programs, (high-end games; Photoshop; etc...).