I would try here for drivers. http://www.sagernotebook.com/drivers.php?cat=601 I did a fresh install of 8.1 and installed drivers from here with no issues. For the dGPU issue it could a couple of things. First try fn+esc if you have the hot key driver installed it should pull up the clevo control center (I can't remember if there is anything other than fan control in there, but I think there is power options in there) also check the nvidia control panel to see if the default 3d settings are optimal, intel, or high performance.