While using start8, after about 12 hours of use, I would have the following things occur after updates issued a couple weeks ago.  1: Final Fantasy XIV and Starcraft 2 would freeze upon logging in or starting a game (sound would play but I could not move or do anything), firefox would load up the tabs but freeze on a refresh of them, explorer would randomly freeze up or freeze when I typed a letter in the search box.  I also have had the start menu freeze with typing in the search bar.  What lead me to believe it is something to do with start8 is that after a OS install and updates applied, explorer would crash and the default UI would appear.  The machine is a custom-build and I highly doubt viruses are the culprit.  Consulting task manager when the freezes in games occurred told me the games were not responding.  The solution was to do a PC reboot and that fixed things for about 12 hrs maybe more-I never clocked it.  Until I know what the cause is, I have start8 uninstalled because the issues seem to start there.  PC is running windows 8.1 pro x64 on a 32 GB i7-5930k unlocked CPU.  I have no logs to look at of any kind relating to the crashes-it's as if the OS didn't record the event at all.