Question My CPU is thermal throttling as soon as it loads into windows, starting up with a CPU temperature of 75+ degrees Celsius. Why is this happening?

Mar 30, 2021
I am running a Ryzen 7 1800x with a corsair h100i v2 AIO cooler and a Asrock x370 Taichi motherboard, BIOS version 3.10. I'm getting the temperature readings from the BIOS, Ryzen Master and CPU-Z, all the same.

Since the problem started I have tried reapplying thermal paste, updating AMD drivers and setting the fans and pump to max and nothing has helped. On the cooler, one pipe is warm and one is cool which would indicate to me that the pump is working. I can't seem to find anyone experiencing the same symptoms either. I'm wondering if there is any possibility of some kind of driver mismatch. I heard a while back that Ryzen adds 20 degrees to its temperature readings to help with fan control so I'm not sure if this is a factor.

Please send help


one pipe is warm and one is cool which would indicate to me that the pump is working.
That indicates QUITE the opposite, actually.

List of possibles - assuming this is a new unit:
-Pump is not receiving power. [Try different fan headers.]
-Pump is broken, or DOA. [RIP. Nothing you can do here.]
-Pump is clogged from debris that was already inside the unit. [Can't do anything about that.]
-You didn't completely secure the pump head to the cpu. When you were turning the screws, you should keep going and stop as soon as they 'stop you'. [Remove cooler, remove old paste, reapply new paste, and reinstall cooler.]
-If this unit had a protective sticker covering the cooler cold plate, it tore when you were removing it, leaving a bit of sticker on the cold plate. [Remove the cooler and clear off the old paste and what's left of the sticker.]

Assuming this is not a new unit:
-Pump gave up the ghost. [It's inevitable. Replace it - keep the working fans.]
-Over time, the fluid volume decreases and the air volume increases.
This makes a certain, popular radiator mount less favorable in the long run: Is the radiator mounted in the front with the tubing entering it from the top? If yes, then it needs to change.
Turn the radiator 180 degrees so the tubes enter from the bottom. If this is not possible, then mount the radiator at the top. If neither is possible, then the unit needs to be replaced.

-The paste hasn't been replaced after a few years. [Remove old paste, apply new paste.]
-If the pump doesn't die on its own, it'll eventually be claimed by gunk that results from the biocides in the fluid expiring, which doesn't happen often. Mechanical pump failures occur more often than 'organic' failures.