I have the Dell S2417DG as well and I've tried this with all of the settings you have listed. But I can't seem to get it working. I've tried both normal reboots and the restart64.exe from the Geforce Forums, neither of them seem to work. No matter how many times I try it doesn't want to enable. I even went back to the 418.81 Drivers that you guys used instead of the current 419.35 but that didn't work either. Any Ideas of why this is happening? Thanks.