I have a Athlon x2 5400+ 2.8ghz (Brisbane) with the stock AMD cooler and a 120mm Antec fan on the back. What is worrying me is, when at max or gaming, the temperatures go as high up as 67-68 C, while at idle it is only at around 38-40 C. Is this normal or is this a problem? I am quite worried. Thanks.
Yeah that's too high. It sounds like an old computer, so the first thing I would do is open it up and clean out all the dust, especially from the heatsink. I'd get some new thermal compound (doesn't matter too much the brand for your applications) and reseat the heatsink. Use 99% isopropyl alcohol to clean off the old compound and a lint free soft cloth. What's the cooling setup of your case?
Yea, it's a 3 year old computer with a cheap case. I've basically got the stock AMD fan & heatsink on the CPU, with a 120mm Antec fan on the back slot. The Antec PSU has 2 fans for intake & outtake.
Now that I remember it, when I added on the stock AMD fan and heatsink couple years ago, I dont remember using any thermal compounds, but when I take off the heatsink there is still white stuff on the CPU?
Check if your fan is running fast enough. I bought a 6400+ and realised the fan was only running at ~500 RPM. If that's the case for you, go into your bios and set Smart fan or something like that to OFF.
I had one where the board thought the CPU was at 0-10C and thus Shut Off the fan. Fortunately I was checking to see if the fan was working and notice, and thus had to turn off smart fan until a BIOS update corrected the issue.