So Today I decided to try setting my monitor to 256 colors, thinking this would eliminate some dithering. I made the change and did notice a little difference, but as I was browsing the web, I went to open a PDF, and when the PDF screen was loading, before the PDF appeared, it shows a dark gray background, and right in front of me, clear as day, it was flickering. Once the PDF loaded the flickering stopped, but I repeated the test 3 more times and every time, when that preloading background was loading, flickering.
I don't think these monitors (Dell P2214H) have PWM, would temporal dithering cause that flicker? It is an Intel 5500 HD graphics chip in a laptop which has been cited online as causing flickering problems.