Running hotter than it used to - 2600k + Corsair H75

WildW_UK · June 17, 2019

Looking for some thoughts on what might be happening here. System is an old i7 2600k, Z77 motherboard, and Corsair H75 AIO cooler (single 120mm radiator). I've been running this at about 1.35V and 4.5 GHz for over a year, and I'm sure that when I first installed it I was only hitting around 80C under a full synthetic load. I looked at it again recently and was alarmed to see it quickly jump to about 95C as soon as the load was applied and continue climbing in less than a minute. Yikes.

I removed the cooler, cleaned and reapplied fresh thermal gunk, and saw a few C drop, but not significant improvement. I dialed down volts and frequency quite a lot, and ended up down at mid 80's C with 4.2GHz and 1.24V to the core. This ran Prime95 without errors for an hour (I know, not the most thorough test any more, I'm out of touch), and the temperature was stable so I guess the pump is still working. It just seems really hot for what's now a pretty mild overclock. CoreTemp is guessing an actual TDP of less than 125W at these settings, and the H75 ought to cope with that easily.

Is this what CPU degredation looks like? I've heard that a degrading CPU might need more voltage over time to hold a stable overclock, but that doesn't seem to be an issue. Or perhaps the H75 is not working as it should? I was planning to reuse it on another machine, guess I will find out when I try.

Semper · June 17, 2019

It's possible that the H75 is at it's end. even though it's a closed loop, you still lose liquid over time to permeation/evaporation. It's also possible that corrosion or growth have occurred. Although not common, it's not unheard of for this to happen after extended use.