NeoRete

How are you monitoring the CPU's temp? Is there any way that you could put a thermal sensor close to the heatsink to make sure what you're reading is correct?

Whenever I'm seating a new heatsink I usually work a pea-sized amount of thermal paste onto the bottom of the heatsink with a lint-free cloth and then wipe it off as cleanly as possible (although checking Artic Silver 5 instructions don't have this included - it might be due to the consistancy of the paste, but it still might be an option). Then I apply the pea-sized amount onto a dust-free vinyl glove, and then transfer the paste evenly on the cpu core. You could try to clean all the surfaces with pure acetone and a lint-free cloth before you try putting on the paste (be careful of additives in the acetone).

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