Reloaded Win 10 on M3800 now no 4k resolution

@Fuzzytek1  The built-in display all outputs are wired to the Intel GPU even when you have an NVIDIA GPU. The NVIDIA GPU only works through Optimus as a render-only device. So make sure your Intel Graphics drivers are updated. And maybe check Intel HD Graphics Control Panel (or Command Center, depending on your driver version) to see if you can set something different there?

I thought I went through and verified that both the Intel and NVidia drivers were the latest. I will check again.

The dell driver update utility said to load version 20.19.15.5063_a06. Still no luck.Tried to load latest from Intel direct and got a message about not validated for use please see manufacture. 

@Fuzzytek1  Yeah Intel Graphics drivers direct from Intel typically don't install on laptops.  You can use the "Have Disk" method to force them, but that isn't typically recommended.  But I doubt a driver update is going to be the fix here given that the system worked at 4K resolution from the time the system left the factory, at which point it would have been running a much older driver.  I admit I've never really heard of the max resolution of the built-in display being lower after a clean install.  Have you tried setting a custom resolution even though you shouldn't have to do that?  If that doesn't work, did you maybe nudge the display connector cable somehow while you were installing the SSD?  I would expect an issue like that to knock out the display entirely rather than just limit its max resolution, but that's all I can think of under the circumstances.  A display's maximum resolution is communicated to the system using what's called EDID data that comes from the display's firmware, so I'm not sure how/why your system would now see 1080p as its max resolution.