Question New PSU and now PC won’t turn on.

[SunshineInABag]

Hello,

Specs:
Motherboard: Z390 Aorus Ultra
CPU: 9900k
Memory: 32gb 3200
GPU: EVGA 3080 FTW3
PSU OLD: Seasonic 650w Ultra titanium
PSU NEW: Seasonic 850w Ultra titanium

My computer recently started crashing while playing certain newer games (civ 6 and pga 2k21). I believe this is because I was using a daisy chain cable to power two of the three 8 pins on the GPU. Therefore, I purchased the same PSU but with 850w. My goal was just to replace the PSU itself and then use the same cables from the old one. I also took this opportunity to put in a new M.2 storage in. I then attempted a startup but nothing happens. Completely unresponsive. The only thing is the leds on the motherboard will flash in a couple spots at what seems like random intervals (2-8 seconds). So first I took out the m.2, nothing. Swapped back to old PSU, nothing. Took out gpu, nothing. I messed with a couple peripheral cables but idk why that would change anything.
Thanks for any help.

edit: It was one of the sata cables that prevented startup.

 

[--SID--]

Reset motherboard BIOS!

My computer recently started crashing while playing certain newer games

You get the same issue with

PSU NEW: Seasonic 850w Ultra titanium

It's a known issue when 3080 FTW3 is combined with Prime Titanium PSUs. You have to look for a non Seasonic unit like Corsair RMx/HX (not AX Titanium because that's Prime Titanium too), XPG Core Reactor or Fractal ION+ Platinum.