Game freezing when loading

I'm having a problem with Windows 7, after I start loading a game(after the screen goes blank) sometimes the system locks up and I can't recover. I am unable to open task manager or get back to the desktop, the only thing I can do is reboot. Any help with this would be great.

OS Version: Microsoft Windows 7 Ultimate, Service Pack 1, 64 bit
Processor: Intel(R) Core(TM) i5-3570K CPU @ 3.40GHz, Intel64 Family 6 Model 58 Stepping 9
Processor Count: 4
RAM: 4037 Mb
Graphics Card: ATI Radeon HD 5670, 1024 Mb
Hard Drives: C: Total - 1907631 MB, Free - 1258942 MB; E: Total - 476821 MB, Free - 440792 MB;
Motherboard: ASUSTeK COMPUTER INC., P8Z77-V
Antivirus: Microsoft Security Essentials, Updated and Enabled