Question CPU reaches 100*C when idle, but 35-42*C when gaming - utterly baffling

Dec 15, 2023
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Yesterday I restarted my new Chillblast PC for the first time, late at night, When it rebooted it was fully throttled. I checked the icue software - CPU temperature was 100*C for ALL CORES. GPU temperature was normal. Fans were at moderate speed as far as I know. A few seconds later it crashed.

I waited and then pushed the power button. It came back and gave me the blue screen of death, followed by an attempted restart/crash into some sort of ‘low power mode’ in which the monitor showed no signs of life, but fans had RGB on and span slowly.

I tried turning it on again, this time managing to see an error message from the BIOS, followed by another crash a few seconds later. Unwilling to risk any actual damage to the CPU (I assumed a sensor failure but didn’t want to push it) I shut it down fully with the power switch at the back.

This morning, I tried pushing the power button but it entered the same ‘low power mode’ when I did so. I rang tech support and they told me about some reseating processes. First I entered BIOS. CPU temp was normal, 26*C. I saved and exited with F10. Then it failed to start the operating system. I unplugged all peripherals barring the monitor.

Finally, it started properly with NO apparent problems at all. This afternoon I played some Baldur’s Gate 3 - each CPU core barely cracked 40*C and the GPU was under 50*C! It’s normally up to 55*C at light load.

Then, after leaving it idle for 45 minutes just now, with NOTHING open, I wake it up from sleep, lo and behold the temperatures are 100*C for every core again. I even managed to check the bios for a few seconds upon an attempted restart and that said the overall CPU was 100*C too, and now I’m concerned. I have been told to try doing a CMOS reset, memory reseat and graphics card reseat next, but if anyone has any ideas or experience with this, I would love to hear it.


Computing:
Intel core i7 14700KF
Gigabyte AORUS ELITE AX Intel Motherboard
Palit GeForce RTX 4080 16GB
Kingston Fury Beast RGB 64GB (2x32GB) 6000MHz
Solidigm P44 Pro 2TB M.2-2280 PCle 4.0 x4 NVMe


Cooling:
Arctic P12 PWM PST A-RGB Semi-Passive 120mm Chassis Fan
Corsair H100X RGB ELITE 240mm AiO Liquid CPU Cooler


Other:
Corsair RMx Shift Series 1000W Modular PSU
Windows 11
Fractal North Case
 
Restart doesn't magically reset temperature.
It will take some time for cooler to cool down. Depends on liquid temperature in the loop.

It shouldn't. But hard to tell for sure.
Thanks for your reply. It seems you were right about the sleep thing. From now on I’ll disable sleep mode and just use shut down to be safe