CPU overheating...not the cooler...Help please!!!!

darrenkarp · 27 Jun 2021 at 20:34

Hi All,

Weird problem. My 5 year old rig comprising of an Asus ROG Hero VIII mobo and i7 6700K with a Corsair H100 water cooler has been working perfectly until a couple of weeks ago when occasionally when I turned her on I'd get a CPU Fan detection and CPU overheating BIOS warning. A couple of power cycles generally fixed it but I decided on buying a new water cooler just in case it got worse...it did today....

I fitted the new water cooler but the problem persisted until i reloaded BIOS defaults (she had an overclock to 4.6ghz which had been working for years without issue).

The CPU overheating issue always came on on a restart in the morning, never during the time I used the PC (which is on for around 8 - 12 hours a day).

Does anyone know what the issue / problem could be?

Cheers
Darren

ANDARIAL · 27 Jun 2021 at 20:52

Cpu temp set too low in the bios?
Or possibly thermal diode has gone wonky

darrenkarp · 27 Jun 2021 at 20:54

I haven't touch anything in the BIOS for as long as I can remember. When I managed to get into it though I noticed the temp of the CPU was over 80C!

All I can say is when I removed the new waterblock from the cpu to make sure it was positioned correctly the CPU was very hot.

ANDARIAL · 27 Jun 2021 at 20:58

Pump and fans working as they should?
Are the fans and pump connected to correct fan headers if applicable?

darrenkarp · 27 Jun 2021 at 20:59

Yes. When this first started to happen I thought the water cooler was failing which is why I bought a new one. All working as expected but concerned something is wrong.

EsaT · 27 Jun 2021 at 21:32

Obviously would be usefull to test with some heatpipe cooler, but could be that Intel's bubblegum/toothpaste under heatspreader has gone bad.

Though this doesn't fit to "thermal disconnection" between die and IHS:

darrenkarp said:
All I can say is when I removed the new waterblock from the cpu to make sure it was positioned correctly the CPU was very hot.

That's more like coolant not being circulated actively.

darrenkarp · 27 Jun 2021 at 21:34

Could it be that I got the same CPU overheating error due to the new water cooler and it not having enough time for the new thermal paste to bed in?

Donnie Fisher · 27 Jun 2021 at 22:12

Do you have another option or header to power the pump ? To ensure it’s actually running ? It could be your header isn’t driving the pump properly?

EsaT · 28 Jun 2021 at 10:34

darrenkarp said:
not having enough time for the new thermal paste to bed in?

Most TIMS don't need any time at least with proper pressure cooler mounting.
And anyway difference wouldn't be many degree.

If coolant circulates properly one tube should be good amount hotter than other when ever CPU is hot.
If tubes are equally warm then coolant doesn't circulate or block doesn't transfer heat to coolant.

newuser · 30 Jun 2021 at 23:32

Do you have Asus Armory Crate installed and is it pending an update? I've seen similar symptoms on start up a couple of times but I believe it was a live service and reporting issue rather than a hardware issue. On both occassions updating the Asus software fixed it.

Shawreyboy · 1 Jul 2021 at 15:21

EsaT said:
Most TIMS don't need any time at least with proper pressure cooler mounting.
And anyway difference wouldn't be many degree.

If coolant circulates properly one tube should be good amount hotter than other when ever CPU is hot.
If tubes are equally warm then coolant doesn't circulate or block doesn't transfer heat to coolant.

The physics in this post is bang on the money. If the AIO is working correctly, the outlet pipe from the RAD to the CPU is going to be cooler to the touch than the outlet from the CPU to the RAD is.

The possibility of the CPU header failing to drive the Pump is a consideration if a new AIO has been bought. Could try it in a known working fan header and plug a standard fan onto the CPU header.