Why does this happen?

I don't want answers like "call Sony". I just want to know the theories of why is this happenning...

EDIT: It's a slim 120GB bought on Gamestop last December

Powersave mode?

it only does everything :p, couldn't resist.

IT ONLY SAVES THE PLANET

Check the Wires, Plug it into a different Outlet, Check PS3s Settings If you can, google, Call Sony.

If this happens when watching a DVD/Bluray or playing a game, then he has an issue with the system and needs to call Sony.

If this happens when its just sitting there or watching something on the internet then, its the powersave mode. Tell him to look through the system settings turn it off or set it to a bigger time frame.

It is being a cranky PS3 and doesn't want to be played.

I have a feeling it's the power save mode settings..check the settings and change it..

XD! /thread

second possibility is the cable connection...check the outlet and inlet portions, and if all of them fine...it should be the hardware fault. Try to reinsert Hard disk if u can and reset the console to factory default settings( TAKE a backup first)