Question : Cannot disable hibernation in Vista

I never use hibernation, so I want to claim that 2GB of disk space occupied by hiberfil.sys on my Vista notebook . However, I cannot disable hibernation no matter how much I try! As you know, there is no GUI for disabling hibernation in Vista; you have to open an elevated command prompt, and type "powercfg -h off". This is exactly what I do, but hibernation is automatically re-enabled after 5-10 seconds! hiberfil.sys is created, "Hibernate" pops up in Start Menu, and I can select hibernation related options in advanced power settings.

I tried the same thing by selecting "Hibernation File Cleaner" in Disk Cleanup, but the result was the same. When I  do the same thin in safe mode, hybernation is not automatically re-enabled, but when I boot normally, it is enabled again.

Configuration: Sony Vaio VGN-FZ11Z, Vista Businesss SP2 with all security patches applied (I had the same problem with SP1). It's in a domain, and I also confirmed with the domain admins that they don't enforce any power management policies with GPOs. I have another laptop with exactly the same SP and patch level, and I don't experience anything like this on it. The only difference is that it has Vista Home Premium on it.

Could you please help me with this EXTREMELY annoying problem? It's not a show-stopper, but it is still annoying.

Answer : Cannot disable hibernation in Vista

OK, I'll tell you how you'll get that bad guy: MOnitor who's changing the regsitry.
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Power is the path to audit.
Do you know auditing?