Question [HELP] PC wont shutdown, fans keep spinning and turns on the moment i plug it on power.

[guilhermeol]

The moment i plug it, it start up but theres no bios screen unless i also pless the power button, when i shut it down it looks like its going to but starts imediately again.
It stopped when i took the CMOS battery out, but putting it back makes it do that after a while.
It started doing that after i put a old HDD i had here, the HDD works fine.
Its not windows cuz it refused to shutdown even from bios.
Its not the button stuck cuz i took it out the motherboard.
I unplugged everything, even ram, its between the motherboard and psu. I also reflashed motherboard bios.
I dont think its the psu cuz i used it on other Pc i had before that even had a RX 570 in it and it worked fine. Also this Pc bareilly use the power budget.
The real question its, could the cmos battery cause this problem? maybe the motherboard is bad or has a bug?
Other than that the PC works fine, i dont mind using it without the battery cuz i dont change the stock bios config anyway but its just bugging me.

Cpu i3 3240
MB Asus p8h61-m lx3 r2.0
Psu Gigabyte PB500

 

[jojesa]

It started doing that after i put a old HDD i had here, the HDD works fine.

Have you try getting a new CMOS battery? They are quite inexpensive.
Also, if the issues started after you installed an old HDD, that might be the cause of the issue.