I am having this problem, after changing some parts in my PC (CPU,MB,RAM) the PC wont shutdown when I press the button in windows 7, it restarts then i need to go to bios and press the power on/off button. Any clues what it could be ? I installed everithing even the ACPI driver, lan wake up dissabled.... I clearly hear the HDD shutting down, after the restart they spinn up again. I was using the Asus P8Z77-V now I have the Maximus VI gene