PC won't power on everytime

[Taxoz]

so its a fairly new problem yesterday my PC turn on and off fine, this morning i attempted to start my PC, there was light in my power button and my HDD activity light for a split second.
i asked a few friends i know one said my 5vSB rail on my PSU may be dead or dieing 

so i did the following after getting home from work:
1 attempted to start the PC like i always do by pressing the power button - failed,
2 removed all my peripherals ( one of my friends suggested that ) - failed

3 removed all USB cables from ports, unplugged any audio jackstick and unplug it from main, held the powerbutton for 10 sec, replug it into mains.. failed
4 wait 2 mins and attempted 3th try again and it booted

suggestions what this can be, is my PSU dieing? to be fair im alittle scared to turn off my PC again

link to a youtube video of what it did https://www.youtube.com/watch?v=KFjsEuYXc-E&ab_channel=Taxoz

[Poinkachu]

Try doing a paperclip test on your PSU

Also, what is your system spec ?

[Taxoz]

Alright thanks i may try that before replaseing my PSU

my specs are 

Corsair RM series 850W
AMD Ryzen 5 5600X
GTX 1070
G.Skill AEGIS  16GB 2x8GB DDR4  3200MHz
MSI MAG B550 TOMAHAWK 

[Taxoz]

i replased the PSU and it fixed it