Could be a hard disk problem on the packard bell
steps taken so far:
stripped everything out of case and disconnected everything,
placed motherboard with just cpu, and cpu fan on smooth wood surface,
connected just psu power cable NOT the cpu power and used screw driver to bridge start and tried it with on/off switch= power on, cpu fan on with constant red light, no display.
then connected cpu power and used screw driver to bridge start and tried it with on/off switch=red light comes on for less than a second the shuts off, no display
so any ideas what the fault is?