I've tried just about everything, and have looked at several forums for help, but haven't yet found any solution to my problem.
Up until about a week ago, I've been able to run most games fairly well, but performance has recently deteriorated(CSGO has dropped from 200+ fps to below 60 fps; PUBG has dropped from 30 fps to around 12 fps). The game would also stutter with black-flashes, until it alt-tabbed me out of the game. I assumed there was a problem with the Nvidia/Intel drivers and updated them both, but the problem persisted. I then realised that the onboard-graphics was being used for games as apposed to my GPU.
Upon Googling the problem, many forums suggested opening Nvidia Control Panel > 3D Settings, and changing the "Preferred Graphics Processor" for each program. However, this option/drop-down does not appear for me. My monitor is plugged into my Graphics port and not my Motherboard, which is the primary reason for this option to not appear, so I am unsure why I don't have that option available. My PC detects and recognises the existence of my GPU, but refuses to use it for any games that I play. Does anyone know of any solution?
Note: When I access the Device Manager > Display Adapters, and I disable the on-board graphics, my PC reverts to using the GPU and my games function smoothly. However, I have been told that disabling the on-board graphics is a bad idea.
Specs: Processor - Intel(R) Core(TM) i3-4150 CPU @ 3.5GHz GPU - Nvidia GeForce GTX 460 SE Motherboard - Gigabyte H81M-S2PH RAM - 8GB OS - Windows 10, 64-bit