Anything other than Crysis?
Pretty much. Crysis is the most intensive game for the CPU. Search around on you will see that so many people have a hard time just trying to get a constant frame rate on the game let alone play it when they are trying to fix an issue with their system.
You need to look at Steam or some other games to try and test out your system so we can make sure that it is not the system. Using Crysis there is no way to determine if it is the system or game as it is problematic for everyone.