peter wrote:
off hand I would check the CPU and its Heatsink/Fan combo.
is it plugged into the right header on the mobo??
is the CPU seated properly?? Thermalpaste ok??
Is the Fan spinning when you turn on the power??
Has the system sat idle for so long that the CMOS battery went dead and
now all settings in the BIOS reverted to default??

Newer Mobo just shut down if any of the above is not right
older mobo make a sound like you described as a warning to shut
down before you burn up the CPU

peter



correct

the alarm indicates a failed cpu
fan

if the fan is still spinning then it's spinning too slowly

probably got gummed up by sitting

solution is to replace it rather than try to fix it