with win 11 24H2 , cpu and system mobo temp sensors fail on high cpu load.

[mnemonic]

So with the latest win 11 update 24H2 this phenomena started to appear.

On heavy cpu load some motherboard sensors report as 0°c intermittently.

This will be a microsoft introduced failure for sure cause it did not happen in 23H2.

 

[Martin]

Which exact sensor values are affected?
Please provide a HWiNFO Debug File of the failed values.

 

[mnemonic]

MSI MAG Z590 Tomahawk wifi (i7-11700K), it's the motherboard Temp sensors of CPU and System.
Both sensors drop to 0°c on occasion when the cpu load is maximum.
Don't think a debug file is going to help anything, clearly microsoft has done something to change this behavior with win 11 24H2.
The other thing i notice is corsair rgb control stutters also when cpu load is high now , did not happen either before 24H2. So it won't be your problem really.
More like microsoft messing with thread priorities.

 

[Martin]

It's most likely a collision between HWiNFO and other monitoring software that accesses the SIO chip on that mainboard.
Debug File could help to provide exact data, but if you think it won't, then we'll leave it as a theoretical assumption...

 

[mnemonic]

I don't think there is much to assume when it did not occur for a whole year on 23H2,
but the very day 24H2 gets installed it happens instantly. Especially when the cpu accelerates to top frequencies, the mobo cpu sensor drops to 0°.
This is an entirely different problem then when 11th gen came out, it also dropped readouts, on cpu cores, but those were fixed with microcode update iirc.