jr9 :
What monitor do you have?
What resolution have you selected in Windows 8.1 that looks too stretched out? Could you post a screenshot of it also?
I think my monitor is a 19.5 inch, and there was only two resolution options, it wouldn't let me drag the slider in between them. We have tried many different places where you can change the resolution and they all have the same problem.Also, when I first connected my computer to my monitor we did not have this problem. It only happened after the update. We have also had this computer since around 2009, but the monitor I got in December 2017. And the resolution is on 1152 x 864, the highest it will allow me to go.