CPU Overheating

[andreinoplay]

Hello everyone, I have a problem, my processor runs at about 57 ° C idle and at 85+ when I'm playing (of course at that point the computer shuts down). It Happens to me since I passed by this configuration:

CPU: Intel Core 2 Duo E6550 2.33 GHz
Motherboard: Asus P5GC-MX/1333
GPU: Nvidia Geforce 8800GS
RAM: 2x1GB Kingston DDR2 (can't remember the model)

to this one:

CPU: AMD Athlon 64 X2 4800 +
Motherboard: MSI K9N Ultra
GPU: Asus GeForce GTS250
RAM: the previous one + 2x1GB Kingston DDR2

The new components were my brother's (who has bought a new PC), so they are "used". I don't think it could be a ventilation problem, because my case is much bigger than the one he had and it has many more fans (maybe too many xD). I thought it could be a thermal paste problem, since mine was completely dry, so I replaced it, but absolutely nothing has changed; I also cleaned the heatsink and the CPU fan, still nothing. Could it be that the fan and CPU cooler are ruined? I also noticed that, from what Speccy says, the CPU Fan runs at 1770RPM, on average, which seems a bit slow to me (but I could be wrong), because my brother's one runs at 2000 something.

Thanks in advance

 

[Supernova1138]

Are you sure that the heatsink is properly secured to the motherboard. That sounds like the only other thing that could be wrong.

 

[andreinoplay]

how do i know if it's properly secured to the motherboard?

 

[tinyt777]

You should not be able to find any wiggle room between the heatsink and the CPU. Other than that, make sure all screws are tightened down between the heatsink and the motherboard.

 

[andreinoplay]

just done a quick check and it seems to be pretty secured