I think you should reseat it...and check the contact between the CPU and the HSF. I found out my ACF7 is better than my Ninja..albeit being quite a bit louder
Maybe because the Ninja is too big for the push-pin design...or maybe I just didn't mount it right or applied too much/too little paste all the times I mounted the Ninja.
The idle temps are a few degrees higher, but the load temps are lower. With my Ninja and S-Flex F temps were 73 max, now they're like 66...but it's a lot louder.
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