What program to check stability?

[fobose]

Can some one recommend me an application I should run to check stability of an overclocked quad core (q6600)?

I used to use everest stability test for my dual cores but I dont think it is stressing all 4 cores as two of the temperatures are a good 8c below the other cores.

Is prime95 still the boy to use? I used that when overclocking P4 northwoods ;D

 

[fobose]

is Core Temp an accurate application to test for temperature? I am getting 10c higher in core temp than in everest!