Screen size switches to 640 when remoted onto client pc. Unable to make changes to the size

Screen size switches to 640 when remoted onto client pc. Unable to make changes to the size from the Screen Setting.

Once I disconnect, the screen will go back to normal. I sat beside the pc in question and watched it actually switch to 640 when I made a connection from my laptop. 

I have tried connecting to it from 4 different pcs.

All MS and Dell drivers have been updated.