cpu lag help

[Peter_44]

I took out my cpu the one with the thermal paste and fan i put it back . i reinstalled windows 7 but it slow on gaming the day before i could play games on high because it's a gaming pc now i lag badly any help?

 

[RababNoor]

Maybe your CPU Cooler is not properly installed.
Properly reinstall your CPU cooler. Make sure there are no gaps.