Computer (motherboard?) switches on and off fast after playing a game

[samerafach]

Recently after having installed 3080 FE on my Rampage IV Extreme motherboard (I had had dual 970 before), with 4930k CPU and with a 1200W OCZ power supply, I get these random shutdowns. The computer clicks like this (see the link below) for a while, then goes off, then on, and works again. The card works perfectly fine, but these issues happen. First happened with Doom Eternal, and then now with Quake 2 RTX.

That thing flashing is the AIO cooler.

A few notes:
1. The resolutions are perfect... No apparent bottlenecking or any other issues. I'm getting a new computer later, but for now I'd like to understand this.
2. Temperatures are normal. I measured them with both GPU-Z and RealTemp. No spikes are unusual temperature values. GPU ~ 80, and CPU ~ 60.
3. This has nothing to do with how long I play. It just happens at times very often, and at times never happens.
4. With or without OC, this happens.

Any ideas what this could be?

Greetings!

[cljustin@ROG]

Have you tried another PSU? That would be the first culprit I'd check.