FX-8350 source of overheating?

[PeterPinus]

Recently I changed my cpu to a fx 8350 because I had it lying around and I had to replace the power supply so I asked the store where I bought the power supply to change it and add the new CPU but I didn't pay for paste so I don't know if they applied some.

Today I ran Prime95 to check my temps and the CPU peaked at 77.3ºC and the motherboard (ASUS M5A97 EVO R2.0) at 87ºC. At idle I get around 30-35ºC on the CPU and 46ºC on the motherboard.
I am running a 140mm fan intake on the left side of the case, 120mm exhaust at the top, 200mm (came with the case) intake at the front, and my H80i is hooked at the back with two 120mm, pulling air from the back into the case. I don't know if I can improve my temps by reconfiguring the airflow on the case (it is an old aerocool mechatron and gets cramped inside) or if I should just buy some quality thermal paste. Worth saying that for now I am running the CPU at stock because I want to deal with this issue first.

Best regards

 

[Darkbreeze]

I would certainly hope they applied paste, but you never know. It's probably a good idea to get a quality paste and then check. Of course, you'll have to repaste anyhow once you remove the cooler from the CPU, so be sure to get the thermal interface material (paste) first.

More important is the fact that you can't monitor AMD FX series thermals like other CPUs. There is no actual thermal diode that measures temperature in the same way that an Intel platform would. You NEED to use either AMD overdrive or Core Temp with the "Distance to TJmax in thermal fields" option enabled. Temps are not going to be accurate and any monitoring software you are using to try and monitor them by specific numerical thermal properties isn't going to be even loosely correct.

See this, and then check again. If you are more than 15°C distance to TJmax while under a full load running Prime95 version 26.6 Small FFT, then you are "ok". You want to probably see about more like 20°C distance to TJmax or thermal margin under full load on all cores, and 30°C or more distance to TJmax/thermal margin when at idle.

http://www.tomshardware.com/faq/id-2122665/understanding-temperature-amd-cpus-apus.html