win 8 odd startup behaviour

[13thmonkey]

My sons win8 machine keeps selfstarting, by this I mean that it has been shutdown, and appears to be dead, then looking at it again, perhaps a day later, it's in standby. He's not in the house so this is not intentional.

Is this an odd definition of shutdown that win8 uses, the last of these was an update and shutdown cycle, so that should have properly shut it down. Or is there something more interesting going on, it came back from uni with a bunch of adware installed on it, uninstalled that, wondering if I've missed something that this is a symptom of, or is it a normal win8 behaviour.

I've checked bios and disabled OS timed startups.

 

[i7Baby]

Got wake on lan enabled?

Is the Shutdown button reconfigured to sleep?

Has he got a Haswell CPU and non Haswell certified PSU?

Post his build.

 

[13thmonkey]

disabled
shouldn't be the cause as not using button to shutdown
perhaps that's an issue, it's a haswell i3 4160, asrock mini itx mobo, the psu is an old S12 600W seasonic.

 

[i7Baby]

How is he shutting it down?

 

[13thmonkey]

windows menu, just done it now, disabled C6/C7 see what happens