Dv7-1175nr intermittently hangs or shuts down

Some times it won't boot at all other times it will run for 10 - 20 minutes then it will turn off.

I,ve tried to restore to an earlier set point but get a fatal error. I've tried to run system diagnostics, but it crashes during the Hdd test. I.ve run it without the battery with the same result. I've tried reseating the memory and HDD.

I'm running VISTA 64 bit.