I have windows XP, and I just installed a ABIT AV8 VIA K8T800Pro Socket 939 Motherboard - AGP8X and a 550 watt power supply. Everything is working great but I can't power down my computer because it automatically turns on after about 5 secs of turning off. I have been removing the cord at night for the power supply after it shuts down, but this is getting tedious. Any advice?