NVIDIA GeForce 840M Will Not Work

[KoreanSpa]

When I try to open games that default to my NVIDIA graphics card, they refuse to load anything past a black screen, yet still play music and allow me to interact with objects that should be where I click, such as the quit game button. If I go through my device manager and disable my NVIDIA card and use the Intel HD Graphics 5500 card, I am able to play any games without any problem, with the exception of slight lag. I have tried reinstalling Windows then reinstalling everything that I usually use, and that has solved my problem for a couple hours, but after I closed and reopened my game, it had reverted back to the black screen problem. Will appreciate any suggested solutions to my problem, thank you in advance

My Specs:
ASUS Q551LNB

Intel(R) Core(TM) i7-5500U CPU @ 2.40GHz, 2394 Mhz, 2 Core(s), 4 Logical Processor(s)
NVIDIA GeForce 840M with 2GB
Windows 10 Home

Please let me know if you need any extra information!

 

[hang-the-9]

Likely a failing video card, although if the system did not come with Windows 10 originally, the driver and OS change may have caused this.

 

[KoreanSpa]

The model is a discontinued model that was sold with Windows 8 installed, so that may be the problem. Thank you for your answer!