Question Intel i5 6600K CPU Overheating on Low Load

Apr 2, 2020

Before I start, here are my PC specs (was built in the summer of 2015, so at the time of posting it is almost 5 years old).

CPU: Intel i5 6600K (Base Clock)
Cooler: Corsair H60i
GPU: ASUS Strix GTX 980
Memory: 8 GB Corsair Vengence LPX 2400 Mhz
PSU: Corsair RM550 80+ Gold
Storage: 256GB Samsung SSD + 1TB Western Digital HDD
Case: NZXT Phantom ATX Mid Tower
Accessories: 4 LED Corsair Chasis Fans

I built this computer almost 5 years ago and have not replaced or added any new parts since the day of install. I have never had any problems with it until about 2-3 days ago. I have been playing a lot of video games recently due to the COVID-19 pandemic and being pent up inside, mainly been playing League of Legends, Minecraft (with mods), and a little bit of Warzone. For the first few weeks of the quarantine, my computer ran perfectly fine, no frame drops or anything, just like normal. That is until about 2-3 days ago, I was noticing my computer slowing down a little bit but just assumed it was due to the heavy load that I have been putting on it that day.

I then went to clean my keyboard and thus hooked up my backup keyboard and loaded into a game of League. Immediately there was a frame drop off and I would dip between 15-30 fps if I was not idle and it made the game unplayable. I then restarted my computer and instead of loading Windows, it went to an error screen saying "CPU overtemperature error" and so I went into the BIOS and saw the CPU temp was fluctuating between 88-95 degrees.

After seeing this I shut down, turned off the power supply and cleaned the inside of my PC and replaced the thermal paste (it had been a little while since I cleaned my PC but the dust buildup was not catastrophic, and it had been about 6 months since I last replaced my thermal paste). I then let it sit a bit longer and then powered up again and it ran fine for about 10-15 minutes then would start freaking out again, and once again on the restart, it was a CPU temperature error.

Over the next couple of days no matter what I tried the problem still persisted and now I can barely even use Chrome or listen to Spotify without my CPU reaching 89-97 degrees. It is also not anywhere near its limit on running power as it is around 45-50% in League, 60% in Minecraft, and 80-85% in Warzone, and the temperatures are the same. Even when I'm just using Chrome and Spotify with 20-25% CPU usage the temperature is in the high 80's and 90's and my computer is unbearably slow and overheating.

I don't know if my computer is on the latter end of its usage or it is something fixable, any help would be immensely appreciated. (Side note, the cooler is functioning properly, so I don't believe it is a cooler issue but I may be wrong.)

Thank you
Last edited by a moderator:
Feb 17, 2020
Not saying this is your case but I've had 2 cpu's over the years die slowly and both started over heating with no load on them. Blow all the dust out if you can level side panel off. Good luck