Question one core running hot

[DuaneWhitney]

I have a 9950x with a MSI Carbon motherboard, and nzxt 360 water cooler. at idle, all cores are around 20-30 degrees. under load, most cores run around 40-50 degrees. one core runs hot, anywhere from 60-85 degrees depending on the load. is this something i should worry about? i used the thermal paste that was pre-applied to the watercooler--looked fine. I'm wondering if the coverage wasn't good on the thermal paste, and may need to reapply.

I noticed that the cpu cooler only displays the average temp (~30 degrees), so didn't notice until i saw the board was displaying the max current temp. i used HWMonitor to see what was gong on.

 

[TerryLaze]

Look in your bios and look at the CPU tab, my guess is the mobo has aggressive settings for PB (turbo) or even PBO (overclock) single core boost can make the core run hot if it's getting pushed beyond stock, did you check if it's always the same ones?! CPUs have best and preferred cores and the OS will send workloads to those cores, it's usually two cores.
https://www.anandtech.com/show/15137/amd-clarifies-best-cores-vs-preferred-cores

85 is not dangerous for the CPU although it is on the high side.

 

[Rokinamerica]

Depending on what you are doing/playing, many apps/games only use a single core so under load that could be the reason.

 

[DuaneWhitney]

Thank you! I think you're correct.

I tried turning off performance boost and game boost. It still runs hot.

I also tried loading each core with a load, and they all run hot -- around 90+. I'll need to tinker with the settings to figure out how to limit temps.

It wouldn't matter for gaming. But I run simulations for about a day at a time on all cores, so I'm concerned about the high temps.

 

[DuaneWhitney]

I turned on PBO and set max temp to 75. That seems to do the trick. Not sure how much it'll impact performance, but is still likely 50x faster than my work computer.

 

[DuaneWhitney]

thanks again for your help Rokinamerica. Saved me a lot of time sorting it out.