I don't know as much as the others here, but I can say I experienced something very similar to what you described in Blender recently too. It drove me nuts for days. Finally I figured out it must have been the driver update I installed to my geforce gtx card from my geforce experience panel. I contacted nvida for help, and they directed me a page that walked me through how to roll back the driver update. Sure enough, after I did that and rebooted my system, Blender began working fine again. This wasn't Blender 2.78 though. It was maybe 2.76 or 7. Anyways good luck. Hope you can figure it out.