Weird restart issue

[_lecro_]

Im in the process of doing a bit of an upgrade on my finance's sons PC..
It wasnt working when i got it. no power it seemed but after taking it to bits and rebuilding it started first time.
ive got an SSD , new OS , gpu and a few other bits coming but the problem atm is when the pc is shut down it just boots up again after a couple of seconds.
I did think it may just rectify itself once the new OS is installed and fresh drivers installed but thought id see if any one had any thoughts what could be causing it to do this

 

[_lecro_]

Yea looks like the diagnosis will have to wait until the new HD arrives Saturday,
hopefully once the new OS is installed all will be good but ill keep you posted if not

 

[_lecro_]

Mmm ok well new OS installed . BIOS updated . CMOS cleared
still refuses to switch off , even with switch isolated .
starting to think the mobo may be fubar but apart from this minor issue it works fine