Question Computer only shuts down with thermal event when booting into Windows.

This is an older Dell Optiplex 330 Running win 7 to run some older programs. Recently, it's been shutting down and upon reboot stating Shut down due to thermal event. This ONLY happens when booting into windows. When I booted from a diagnostic USB stick it stayed on all weekend without shutting down. When I ran Dell Diagnositc (f12) it went through the whole hour long process, did not shut down and did not come up with any issues. I opened it up, cleaned it out, replaced with new thermal paste, the heatsink doesn't get overly hot to the touch upon start up, and the thermal event ONLY happens when booting into Windows, either full boot or safe mode. The machine also ran from a Live USB Ubuntu without issue. Could it just be a driver issue? Im usually very good at figuring this stuff out but this one has me stumped. Thanks in advance.
 
Jan 9, 2019
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Have you checked the fans to see if they are working correctly? Hwinfo can look at the CPU and core temps along with Hard drive temps on some drives. It will also show you the RPM's on the smart fans. You can also check in the BIOS and see if you have it set to Shut down the PC if the temp gets to a certain temp, or shutdown if a Fans RPM gets to low.
 

Randi Poling

Distinguished
Feb 19, 2014
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Hmm... i would potentially check the themral compound. it is possible it has dried up. I dont think dell uses the best compound on their systems and I have seen some where it was super spotty and didnt really have much at all.
 
Jan 9, 2019
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60c startup is too hot. I dont even get that on full load. Im not running water, just a Regular Air powered Cool master. My startups are 27c. My idle is 31. I never hit 42 even under a full load.
 
Idle temp for this pc is
Intel Core 2 Duo45°C - 55°C
I'm pretty much within that range. high operating temp at full load shouldn't go over 80°C, so I am still well within normal operating temps.

Its fine. I'm just gonna scrap it... no point in messing with it much further. I think the CPU is probably toast anyways.