Just recently and suddenly, Windows10 is showing CPU over heat warning messages. My system is an Intel i7 2600K (with no overclocking) on an ASUS P8P67-EVO Mobo.
Initially, I noticed that some applications and the system slowed and sometime locks up. This got worse as time went on. I ran several system temp applications, and they all confirm CPU high temps (far above 80 c) at idle. I use an H50 water cooler. BIOS (updated and confirmed) showed that the cooler was running at only 1000 RPM, so I replaced it with an H55 cooler. The H55 showed a higher pump RMP. But at times the new cooler started showing lower pump RPMs (roughly 1190 RPMs). The new cooler did not resolve the over heating issue. In further troubleshooting steps, I reseated the processor, replaced the thermal paste (twice), and installed an air cooler. None of these fixed the CPU overheating problem. I did not replace the processor because I do not have an extra 1155 processors to try.
In BIOS, I can watch the temp increase to warning temps within minutes after system startup.
How do I know which item to replace? How do I determine if this issue is a bad processor or a bad Mobo?