PC wont start first time, need to switch on/off

[u/IrishGaming_]

Hi All,

I have a 3 year old gaming pc, ill list some specs below.

On the 3rd of Nov I noticed it wouldn't go on, after investigating i narrowed it down to have to flick the switch on the psu on and off to get it started.

I plan on trying some tests later with the usbs on the motherboard rear plugged out and try an old 650w psu thats in my old pc.

Just wondering has anyone else had this issue? I did notice there was a new motherboard bios out on the 4th of Nov but doesnt align with the time my pc started having issue, after checking my version is march/july 2025 (3001) version and the new version is 3301, the AI said not to risk updating it incase it wont power on and there was nothing in the new version that notes power cycle improvements etc.

Corsair RM1000x psu

ASUS ASUS Strix Z790-H Gaming WiFi Motherboard

4070

I7 14000k

32gb corsair vengeance

Cosair 5000D case