Issue
Computer boots up momentarily and up comes an error message stating that there is a CPU Over Temperature Error. Be rest assured that most modern computers will auto shut down when the CPU reaches an unsafe temperature to avoid further damage. Hence the “crashing” if you experience it as well.
Environment
Platform/Operating System: Windows 7 custom PC
Solution
Replace the heatsink. In my particular case, the heatsink happened to be a Corsair CPU Liquid Cooler and was obviously failing. Upon numerous boot ups in an attempt to inspect all the case fans and making sure everything was plugged in and memory seated correctly, I heard a noise that did not sound normal coming from the pump. This pretty much hinted me that the heatsink was the issue.
Here’s a neat video that demonstrates the process of How to Upgrade CPU Cooler // How to Replace CPU Cooler or Heatsink
Conclusion
I replaced the heatsink with a compatible equivalent and booted up numerous times without issue. Running applications and leaving it idle for some time to test out stability. Replacing the heatsink when you get the “CPU Over Temperature” error message solved my problem. Had there not been that weird noise, I would have removed the heatsink and replace the thermal paste. And if that didn’t work, I think I would have swapped out the heatsink to rule it out in any case.
Important Note
This may or may not work in different environments and you should always remember to back up your data before making changes or applying any solution regardless of source.