i will put my two sense in on this discussion and im not trying to be rude by any means so please do not take it that way. Enscape is much like any other real time engine, and with high quality real time experience comes with a large hardware demand. A gt720 and a gtx 960m have performance ratings below 2200, the gt 720 does not even break the 1000 mark. These graphics processors are just not designed for this type of work and will never perform as you want them to. To give you some comparison, a 6 year old gtx 580 that can be picked up for 45 bucks on ebay is 5 times more powerful and a new generation 10 series is 12+ times. If you are using enscape as a tool to produce images, animations VR etc you must also have the other tools to go along with it. A fast processor, decent amount of ram and a good graphics card. Using an under powered card for this type of work is like trying to drive a nail with a spoon. go get yourself a hammer and you wont regret it.
I know a gtx960m is sold as a gaming card, but it really is not and has poor performance for compute calculations. Not many games in the world that actually keep your graphics card at 100% the entire time.