[SOLVED] "first boot" cycle every time PC has been unplugged

[crash bash]

well hello gentleman, for the last 4 years my pc works just fine.
but 2 days ago, it start doing a wierd behaviour. every time after the psu has been unplugged/turned off next start will do the "first boot" cycle, where i start the pc, it will turns off after a second and then starts again to the "first boot" cycle and then it will boot into win 10 normal. If I just shutdown the pc without turning off the power supply and start it, it works like normal. so it is something that causes this when there is no power to the system, any help will be great.

 

[rgd1101]

full system spec? include brand and model of the psu

 

[crash bash]

full system spec? include brand and model of the psu

i7 7700k
Asus strix z270E
Arctic freezer 360 (aio)
rx 580 8gb

T force 16gb 3200mhz (8x2)

Samsung 850 evo 500gb
Corsair RM 650x

 

[DRagor]

Two immediate suspects are PSU (you have great unit but even great units fail sometimes) and motherboard battery (4 years might be about the time to replace it). If you have a spare PSU it would be good to use it for a test, just make sure to swap the PSU's cables too if you use different model.