the CPU and the HS Fan is working properly, the only other alternative is to replace the CPU HS and Fan.
I'd start by checking to see the HS is flush and secure on the CPU. Lots of good CPU HS Fan info over at http://www.Frostytech.com.
Let us know how it works out.
I took my pc to a friend a few weeks ago to clean it and he wanted to test a cpu on my PC so I let him, after that he said that I have to change the thermal compound and he chenaged it but after that I noticed that the cpu is overheating when i play ( i play only cs 1.6 and warcraft frozen throne) and reaches 100 celsius degrees (I saw this temperature in speccy) and often the pc is shuting down. Two weeks ago I decided to change the thermal compound and I bought Arctic Silver 5 but there is no big difference and i have to mention that now the pc is properly ventilated and the problem still persists, if the problem it's not from the thermal compound or the ventilation what could be?
My processor is an AMD Athlon 64 X2 4200+