If the hardware supports both S1 & S3 power saving modes (Standby & Hibernate), it's possible.
Not all hardware supports both power saving modes. You'll have to check in the BIOS.
Is it possible to set windows up so when the ignition is turned off the carpc goes in to standby then after say 25 minutes it will go in to hibernate? I know it's possible in Vista with my laptop but is it with XP and a desktop?
Yeah it does, but when I run centrafuse and emulate ignition off it goes in to standby as I want but I have windows powermanagement set to hibernate after 3 minutes (for testing) but it doesnt just remains in standby?
I don't know of any carpsu with this feature at the moment. I've successfully done this using windows xp before but never was able to do it in the car.