Remove the cpu hsf and clean off the old paste.
Apply a new layer and install the hsf.
Test.
While you've got the hsf off give it a good cleaning.
A small brush might come in handy.
Alright folks, I have had this pre-built HP Pavilion (p6-2127c) and I have been playing games on this since like 2013. The CPU has been fine. Then one day, in the middle of a game, the CPU fan started going really loud. I decided to clean it with dust-off and a rag. Then i played CS again for a little bit and then the fan went crazy loud again. Like the RPM Goes way up. So I found out that my processor has been going to over 65 degrees Celsius. And just barely has it been getting that hot. So it has been cleaned with compressed air and a rag. What do I do?

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