Random lag spikes in all games

Hello everyone i was hoping maybe you guys could help me with a problem i have been trying to fix for awhile now. For some reason in just about every game except skyrim I will be running at a normal 60 fps or higher then all of a sudden my fps will drop down to around 12-15 fps for no reason what so ever. I have updated my bios, updated my gpu, changed video cards to see if that was the problem, heat never gets over 54 degrees on my gpu or cpu, done a memtest, and have turned off amd cool n' quiet after hearing it has caused problems. Idk what to do at this point for i have tried alot and i'm hoping you guys will be able to help me out.

specs-

AMD Phenom(tm) II X4 955 Processor~3.2GHz
NVIDIA GeForce GTX 460
2 2gb sticks of 1600mhz DDR3 ram
xtremegear 700 watt power supply
ASUS m4n685-m v2 MOBO