I tried disabling USB 3.0 and that didn't work. Now that everything is set up the way I want, I really don't want to format and re-install, especially since I've already activated Windows. I think it does have something to do with either the network interface or the bluetooth module though. My old desktop has the same copy of Windows 8.1 installed on it and it sleeps just fine. I may just deal with it since networking works, and the last time I installed the drivers it stopped working Luckily the system boots up very fast anyway, so it's not a huge deal, just very annoying.