It's a Razer Naga Epic. The trouble is that (I) it needs to be charged through the charging dock (which is connect to the PC by USB) and (II) the dock doubles as a dongle, so connecting it to a power strip means I can't use it on the PC.
That's why I'd like to charge it through the PC when the PC is off: right now my only options are either to (I) leave the PC on to charge it when I'm not using it or (II) stop using it to charge it or (III) disconnect the dock from PC and connect it to a wall outlet everytime I turn off the PC. I've been going with (III), but I'd really prefer not to have to.