CPU Temperature too high

[danboris]

I put together a system and am monitoring the temps and the system idles around 52-54 C and gets up to about 69-70 C under full load. I had a stock heatsink and fan and recently upgraded to the Thermaltake Venus 12 with Arctic Silver 5 for the thermal grease. I have one 80mm intake in the back and one 80mm outtake on the side for case fans. I don't know why the temps are so high. Any suggestions? Thanks.

System Specs:
Abit AV8 Socket 939 Motherboard
Athlon 64 3400+ Socket 939
Kingston HyperX 400MHz 512x2MB
Thermaltake Venus 12 Heatsink and Arctic Silver 5
ATI Radeon 9800 Pro 256MB
WD 80MB HDD 8mb buffer 7200 rpm
Case is made of thin steel (Any great effect on temp?)
Cooln'Quiet Technology is enabled and the voltages all seem to be right

[Marcin]

Hi,
Some mainboards overstate temps so If you correct place Arctic paste that will be good