Which operating system and program are you using to measure wattage? Sometimes some programs like GPUz misread the power state and read it as one level higher which would account for the 20w difference sometimes under Windows. I'm assuming the fan profiles and RPM are the same. It's possible they made hardware changes on Rev 2 but I haven't pulled mine apart to compare my rev 2 to pictures of rev 1.
Sorry for the delay on this, the modified bios is on my windows OS drive, I've recently switched to HiveOS. I just need to retrieve the bios from the windows drive and I will send to you. Unless I can do this out of HiveOS, I'm really not very familiar with Linux, at all.