Discussion PSU repeatedly clicking when trying to boot up


Minimal Tinkerer
Original poster
New User
Jul 29, 2020
CASE: Sliger sm550
CPU: Intel i9 10900k
GPU: Nvidia ASUS GTX 970 Turbo
PSU: Corsair SF750
AIO COOLER: Asetek 645LT with Noctua NF-A9x14 HS-PWM
RAM: 2x Corsair Vengeance DDR4 16gb
MOTHERBOARD: MSI Meg z490i unify
FANS: Noctua NF-P12 redux-1700 PWM

Hey all, I recently ran into this sporadic issue of the PSU repeatedly clicking when I try to boot up, unsuccessfully. Basically what happens is when i press the power button on the case, the PSU clicks and the fans run for a half second before turning off, and this process repeats until I cut power to the PSU via the switch in the back. It randomly happened twice before, and previously, cutting off power and rebooting fixes it, but today it kept happening.

I tried several methods such as removing all the psu cables from the motherboard and GPU. I then plugged cables in one by one to see where the issue occurred. The motherboard cable was fine, but when I plugged in the CPU power cable, the clicking issue happened again. So then I thought it was the CPU cable that was faulty or a short somewhere, but I had a spare PSU to test, and I swapped PSU's into different PCs, and everything works fine, even with the CPU cable from the SF750 plugged into a different motherboard. I'm lost and confused as to what could be the problem. Any help is appreciated


Shrink Ray Wielder
Jan 25, 2018
I suggest taking the entire system out of the case. Have the mobo sitting on something non-conductive and begin the trouble shooting there.