Cpu overheating due to power supply?

chowks · 30 May 2020 at 10:35

I have been having a few strange issues with my PC and was hoping someone might be able to shed some light.

Very occasionally it will not boot up. I turn it on, the lights and fans come on, but nothing is displayed on the monitor. To fix it, I usually turn the power supply off and on, and it works again with no issues.

This morning it had the same problem, so I tried turning the psu off and on again. After a few attempts it showed the bootup screen, but then a message saying "CPU over temperature error". I then went into the bios and it showed the cpu temp at 98+C! The PC has been off all night and doesn't feel hot, so I'm thinking this must be a misreading. After about a minute in the bios the PC turns itself off.

Here is a pic of the bios showing the settings, if that helps. I'm wondering if maybe this is a dodgy power supply problem? The PC is at least 5 yrs old I think.

Thanks for any help you can give

Akagi · 30 May 2020 at 10:38

The overheating won't have anything to do with the PSU.

I expect the issues have been related to the CPU overheating all along.

You need to make sure the CPU cooler is mounted correctly, remove it, re-apply paste, re-mount it. Have a look at the thermal paste when you take the cooler off, you should be able to see how good the contact patch was.

chowks · 30 May 2020 at 10:42

Hmm okay. It's strange because the PC normally works perfectly with no overheating issues, but will then just occasionally throw this wobbly. The PC wasn't self built but from a reputable custom build company, so one would assume the cpu cooler was fitted properly. Maybe it's come loose...

james.miller · 30 May 2020 at 10:45

Assume nothing, especially when somebody else built it!

Akagi · 30 May 2020 at 10:50

Yeah I've seen some shocking computer builds by "reputable companies"

chowks · 30 May 2020 at 11:32

I think I've (temporarily) solved the issue.

I pushed the cpu cooler power cable slightly to make sure it was on properly. Turned it on and then heard a swoosh of what sounded like water rushing through the cooler. Temps are back to normal.

Thanks for your help. I should've tried this from the beginning!

james.miller · 30 May 2020 at 13:45

Yeah keep an eye on that plug. And the cooler, for that matter. A 5 year old AIO water cooler would have me on the edge

Akagi · 30 May 2020 at 14:03

james.miller said:
Yeah keep an eye on that plug. And the cooler, for that matter. A 5 year old AIO water cooler would have me on the edge

Mine lasted almost 9 years and I only retired it because the temps were no longer acceptable. It was run 24/7 too. (H100)

Current one (spare) is 6 or 7 years old.

DJai · 31 May 2020 at 11:03

It's funny sometimes how something so simple can be overlooked.

It's a bit like when someone asks IT for help and they ask whether you have turned it off and on first.

That can save so much time and cost, glad you figured out it was the plug and fixed it for free.