Ive seen nearly the same problems on all sorts of fourms but never the exact same and a "solution" that didnt work.
2 weeks ago i upgraded my prebuilt. I bought a new gpu, power supply and case. It was fine for a couple days but then wouldn't boot. It would power on, LEDs and fans all work but the USB ports weren't powered. I did some searching, couldn't fix it but then one day it decided to turn on! And then it didn't again. It then decided to be bootable completely randomly. One night I'd turn it off and it'd be a gamble if it'd turn lon the next morning.
I thought the problem was the Mb.
After that i bought a new Mb, CPU and RAM. worked fine again for a couple days. Now has the same problem. This time around however my Mb has EZ Debug LEDs on the board. 1 lights up and that's the CPU. But everything is completely new from the ground up except the storage. So how the hell is the CPU causing this problem?
I've checked wires, repluged everything, tried to boot with 1 stick of RAM and no USB connections, tried different power outlets, And YES I've turned it off and on.
Specs:
Gigabyte Rx 5700
Ryzen 5 3600
Corsair vengence LPX 2x8gb ddr4 3600Mhz
Msi MPG x570 gaming edge Wi-Fi Motherboard
Corsair vengeance 750 watt PSU
Cooler master mb530 Case
I'm desperate here. Spent so much money just to get it too work :(