I currently have an Intel(R) Core(TM) i5-7200U CPU @ 2.50GHz and NVIDIA GeForce 940 MX GDDR5 2GB. Are these parts replaceable or soldered?
You mean "Slot 2: SK Hynix DDR4-2400 (1200MHz) Single 8GB Stick (Factory)"Try a clean setup of Windows, then run the driver updates from Dell support site. Maybe the second RAM stick is causing issues also.