I have the same problem now. I have a laptop with Intel integrated Graphics Card and GeForce 780M. I’ve been using Unreal 4 since summer and it was running smooth until now. Every project started running in 20 fps at best, new or old version. I checked and GF780M is not being used when Editor runs. I’ ve set in nvidia control panel to use proper GPU on every executable from 4.7 and the launcher. I tried reinstalling both intel and nvidia drivers, and Unreal itself. And NOTHING. I recall two things that could cause that: the 4.7 or my recent scan with Combofix. Any ideas?