Go to your process tab and see what is using the CPU. If it's only like that while playing games, most games will push a duel core to 100% usage, many new games can use more than 2 threads effectively.
well i just noticed its not only slow on games but its always like that beside these games alwayes played at highest performance why just so slow all sudden !
the game am talking about is Kingdoms of Amalur Reckoning my reg works perfect for it and it was played smoothly