Acer Aspire 7720 G ?

Are there any known faults with this model ?. I received one on its way to recycle. It started up ok at first but then threw a series of fits with shutting down and not restarting. A PC repair guy thinks it might be either the graphics card or an inverter for the monitor. The pc seems to power up but you are left with a blank screen.The hard disk light is flashing and fan running. I installed Win 7 after the Vista and it seemed a lot happier at first.Usual story you can easily spend more to repair than replace.Any help/advice appreciated........ Martin