_Sixpack_

All is well now. It was the PSU (brand new Corsair AX850 V2) that was broken.

Well, according to the Asus support team I should try starting the system with no memory and no graphics card, just to see if the Q code would get stuck on memory problems. Unfortunately that didn't help. The power was not on long enough for me to even see a Q code.

Thanks for the suggestion. Is that possible to do on a x570 motherboard?

When I start the system everything lights up for a second before the computer shuts down again. Reset of CMOS a few times in a row will make the system start again, but only for a while. Motherboard: ASUS x570 Gaming E CPU: AMD Ryzen 3900x Memory: 4x16GB DDR4, 3600MHz gSkill GPU: ASUS Geforce 2080 Super I built the system in January. The system was fine for a few days. I managed to install a few of my games and play without issues. Then one evening the computer just shuts off. I did not use it at the time so it was just idle. I switched it back on and managed to update the bios to version 1405. Everything was going smootly for a while and then it happened again. Now the computer refuses to post without resetting the CMOS, but most of the time it just stops. I can't see any patterns in the Q-code on the motherboard. It stops randomly. I've tried to use only one memory stick, switched the graphics card to another slot. reseated the CPU just to see if something was bent and I've gone through all the cables from the PSU to the motherboard. The PSU is a Corsair AX850, so it should cover everything. If I make it to bios there is no sudden temperature spikes or anything like that. When the system was working I would see idle temperatures of 35-40C. Please help