Any help on this would be welcome .Yesterday my pc a hewlett packard t685 stopped with a going to sleep message on the screen.Up to that point it was working fine.On Re-booting the green led lights on the monitor then changes to amber displaying the going to sleep message again.There appears to be hard drive activity and there are no discernable beeps to indicate any bios problems.I have checked all the psu voltages and all are ok.The only thing I have noticed is on the graphics card an ATI Radeon x600 pro the cooling fan is not operating .Does this only run when cooling required or should it run continuously indicating a possible failure of the graphics card cpu due to overheating .