Hardware problem. Either RAM, mobo, or CPU fan:
RAM:
Use a pencil eraser to clean the RAM module pins to remove static.
CPU fan:
Remove the CPU fan. Open it up using appropriate tools. Remove the grease and the dust that built-up. This is what is causing its slow turning. Then re-grease it and re-assemble it back. Put it back.
Mobo:
Buy a new one.