QUOTE: The graphic driver problems may be due to not having 8.1 on this system
QUOTE: Use the latest version of the OS, AV and Drivers. Doing anything else is asking for problems.
Windows 8 is still supported with Microsoft Updates! Moreover had most severe problems with Update / Upgrade (of Windows 8 from DVD) from Windows Store to Windows 8.1 on one computer, other computer not, only difference Microsoft Account I was logged in with during Upgrade, the problem Windows 8.1 did not look like real Windows 8.1 and did not behave and work like real Windows 8.1.
Both computers (problems and no problems) where secured with Avast 2015 Internet Security (out-of-the-box default settings)