I've never had power increase with USB device on a few 700 series boards and I use 5 USB attachments daily [KB/Mouse/USB-D/P-Tuner/Nokia]. Kinda strange that it actually puts a high load on the CPU (I/O load), looks certainly like a device specific feature.

My DFI picked up in morn by a friend, its not knew, package was opened but its giving me C1 as well, same as on MSI, Abit and GBT boards.