On my HP 625 motherboard is broken. The north bridge, based on AMD chip, is overheated, and HP 625 can not start.
HP 625 switches on from time to time (mostly it does not start). It may start now, but can not start 5 minutes later.
Generally, after switch on power button of the notebook, Caps Lock key blinks 5 times, the screen is blank and nothing happens anymore (bootloader, operating system is not loading). It means that North bridge on the motherboard is broken. As I understood it is the typical problem of HP 625 notebooks.