ASUS Rampage IV Gene: Can it be downclocked to conserve battery power?

[PCN00B]

Building a car PC.
Wanted to know, with the ignition off, is it possible to set the mobo to underclock the CPU and in essence be a power sipper?

 

[pwnmachine]

Im not sure if you could set it to change with ignition but there are power saving modes you could enable(in software and bios) but they would have to be manually changed. There may be a way to rig it to change when the ignition if off but there is no set method that I know of.