Well your
G751 is about 3 years old now. so you might be ready to upgrade.
In the meantime most likely WU ran a driver upgrade for you and has your Nvidia card all screwed up. the solution is to first download the latest Asus approved version of NVidia drivers. that should get you back up and run. then you can download the latest from Nvidia website and give that driver a shot.
Our notebooks don't like all the WU native hardware drivers and from time to time we have to reinstall known good drivers.
If you have a pro version you can use GPEDIT to block all driver updates then manually upgrade your hardware drivers as needed and you know are safe buy what people on here are reporting.
Actually, you should have an Image stored on an external drive that you can restore that will tell you if your problem is software or hardware. If not for future reference
Macrium Reflect is a very good program and the free version would save you from a problem like this.
If drivers don't fix you it is possible that a connection cable from screen to MB has become damaged or loosely connected? Any quality computer shop that works on Notebooks should be able to solve this for you if that is the issue. Beyond that, it's probably not worth repairing as MB are quite expensive.
G752VY-DH72 Win 10 Pro
512 GB M.2 Samsung 960 Pro
1 TB Samsung 850 pro 2.5 format
980m GTX 4 GB
32GB DDR 4 Standard RAM
Z97 PRO WiFi I7 4790K
Windows 10 Pro
Z97 -A
Windows 10 Pro