After shutdown machine reboots without input

Do you have a question? Post it now! No Registration Necessary.  Now with pictures!

I have an AMD 64 3200 venice core machine built on an Abit AN8 Ultra
board with 2X256 mb modules of Elixir ram, Asus Ax300SE video card
Maxtor 160 gb Sata drive and Pioneer 109 DVD rewriter in arianet case
with a 450watt power supply.

When I put the machine into standby modeor hibernation the machine
frequently restarts immediately after it has gone into
standby/hibernation, or it may decide to wait for any period of time
from minutes to several hours before it bursts spontaneously into
life. This also happens, but much less frequently if the machine is
fully shutdown.

I have disabled all wakeup events in the bios so that the only way
that I can awaken the machine is to press the power button. I have
tried removing the lead from the power button to the motherboard so
that I could eliminate a faulty power switch. Nothing solves the

Can anyone suggest what may be wrong, or have I just got a bad
motherboard? the spam to reply)    
   I've taken a vow of poverty, to annoy me send money

Site Timeline