Not sure why this happens but it has happen on 2 different motherboards AND not just Ultimate Edition. I have 2 mice and I'll be using the Rev for a bit then it'll sudden stop working then I grab the G9 and use it for a bit then it'll stop working. Then I'm forced to shutdown with the keyboard (at least it still works). It would be nice to know why the mice stop working all a sudden.
Maybe the nvidia problem is also causing a mice problem. I only say that because both board are nvidia sli boards.
When searching for a solution on here I found this viewtopic.php?f=7&t=3062&start=0&hilit=Mouse+stops+working Looks good I wonder if it is 10.10 compliant. Maybe it's a G15 problem I probably need to see if a bluetooth mouse has the same problem.