buying a different cpu cooler

[memory]

I currently have a Arctic Cooling Freezer 7 Pro and I would like to get a different one. One reason is my temps seem to be a little on the high side. 2 of the cores idle at mid to upper 40's and the other 2 cores idle at mid to upper 30's. Why such a big difference? Does the Cpu and cooler need to be lapped?

I would like to have one that I could install without taking out the motherboard but I will if I have to. What are some good ones? How big of a difference would it make in temps?

What about thermal paste, does that make a big difference? Right now I am using Arctic Silver 5.

 

[Fat.Clown]

grab the sunbeam corecontact freezer

uneven temps could be yes, the heatsink (both cpu and cooler) have uneven surfaces
or you didn't seat it good eg. TIM didn't spread well

usually lapping will give you better results

if you do not want to remove mobo, which usually is a push-pin style. grab the xigmatech rifle

AS5 is fine