AS: where it counts, by hibernate i mean Suspend-to-disk, not suspend-to-RAM. I wonder, if hardware configuration asked for changes when resuming from hibernate ? I have a notebook with USB1 keyboard-and-hub (Cherry) and an USB2 Flash drive. Keyboard reports it can give 100 mA of current per-port. USB disk reports it consumes 200 mA. So de jure this disk is not to be turned on, or at least Linux is to ask user if he wants to run this device, even he understands it is risky. Ok, this question is not for Power-Management forum. But i remember a couple of pitfalls i met on Windows and do not want to see them in Linux. When i plug this USB dirve into keyboard when Win2003 is running, Windows rejects the device since it requests too much power. But if i put Windows to hibernate, then plug the USB Drive and then resume Windows - it forgets to check for power requirements and tunrs device on (which is useful, but which is a bug :-) ) So i wonder if there are (planned) some measures to test for hardware changes, why PC was hibernated. Another pitfall was with Win2000 and old notebook (iP266MMX, 64 MB RAM). I put Win2000 into hibernate. Then i went to service and upgraded memory. There was 32Mb onboard + 32Mb as SO-DIMM. So i changed that module for 128Mb one, and tried to resume Windows (yes, a dumb idea and i had to think beforehand - but what if i did not?) And what i've got was a blocker. When i resume Windows it usually allows me to enter Advanced options and choose to kill hibernated session and to do a cold boot. This time i just got an error message that RAM amount changed and resume is not possible. If i did not try to resume Windows at the service center, where i could ask my RAM back to shutdown windows - i would be in a very hard situation :-) IMHO correct behaviour then would be at least to allow user to make a cold boot, and the most correct would be giving warning, but them resuming and using only 64 MB of total new 160Mb RAM, untill reboot. Yes, both this examples are quite perverted, but i hope Linux would be able to couple even such pitfalls :-)