On a side note, since I installed 8.1 I also have a problem with my computer starting itself up randomly up to 30 minutes after shut down. I've disabled all fast start features as well as the ability to sleep, the only option available now is that it does a full shut down. It still sometimes starts itself back up without any input from me (I'm out of the room when it happens). The only solution I've found to this one is to switch off the power after shutdown, leave it 30 seconds, then turn the power back on (via the socket on the wall). Again, this is only since 8.1, seems to be some serious issues with this update as I've never experienced either of these problems prior to this and I've been gaming and building my own rigs with various versions of windows for just under 20 years now.