sir i have a big problem with my pc 5 days ago i buy it my pc spec is 2500k i5 processor my graphic card gtx660 twinforzr iii gigabyte z77d3h motherboard corsir vangance 8gb ram i am useing window 7 64bits my driver is 377.88 latest and new sir when i play games like bf4 nfs the run crysis 3 4 or 5 mints after playing games black screen and freezing when i apply ctrl+alt+ delete the option is this game is not responding every game have this kind of problem i install 4 time new window 7 and 7 time change nvidia drivers latest and old every time the problem is same [not responding] it a bad time for if every one know this then please.... help me how i can solved it and its a hardware problem or software tell me