Question System voltage?


Aug 31, 2017
I built a new system with a ROG Strix 690, 12900k and a 3090ti gpu. The power button has a led on it and when I press the button the led flashes twice and then nothing. If I disconnect the 3090ti the system boots correctly. I have a 850w power supply currently and am thinking the only thing that would cause these symptoms is that the 850w isn't enough.

Has anyone had an issue with similar components? This build has already been troublesome with clearance issues, cord management and especially with the AIO needing a special LGA 1700 retrofit kit which contains 4 water block mounting screws that are 1mm shorter than the 115X/1200 ones.

Pulling my hair out here any advice would be greatly appreciated.

Nine Layer Nige

I think that there is a high probability that a 3090Ti AND a 12900k is asking too much from your 850w PSU. This will also depend on the quality of the PSU. What is the make,model of the PSU
If it were me, I would probably buy a good quality well reviewed 1000w PSU.
Dont go cheap on PSU.
Reactions: Rdslw
Well, as you tested without gpu, its either to much power needed, or something is wrong with GPU.
Nvidia recommend 80 Plus Gold 1000W and above. So I would put my money on PSU, Especially if you had to use those 3x8 pin to 12 pin or something like that, it's not a good idea to mix it with weak psu.

I would start by updating bios, and maybe checking other PCIE slots if available.
With such strong GPU, some boards just say nope, thinking its taking so much power, that it have to be shorted out. Sometimes just bios update can solve it.
check on PSU what power split goes where, you can disconnect power from PSU, turn it off, return after 20 min, listen for "clicking" from PSU, if its power draw you should hear one louder or regular faint clicking.

if you have any older mobo, like 9'th gen intel or any amd, they can give you more power for gpu, as 12'th gen intel is also taking like 250W, worth trying if you have the hardware.
if you have any other gpu/network card/anything PCIE, it would be good to slot it as well, to confirm PCIE slots work.

we basically want to cross-check as many combinations of things to eliminate what works.

It can be just gpu bricked. They are not that uncommon, especially if bought of amazon. If you have any box where you can put that gpu, that have more power, just to confirm its not bricked already. You might ask local shop to test it for you.

3090ti's have some kind of fault that bricks them with excessive power draw frying one of mosfet, if you bought used, you might have received already popped one.
this guy shows and explains what is going on: