Desktop bleeding off screen with a downscaled dual 4K setup

@dan2021  I'm not sure what you mean based on your description.  Maybe a photo would help?  But if you haven't already, try setting the desired resolution using Intel Graphics Control Panel / Command Center rather than Windows Display Settings.  Then make sure both displays are set to 100% scaling (which you might have to do in Windows Display Settings) and finally log off and log back on if you had to change the scaling of the primary display so that Windows actually starts rendering internally at 100% rather than using post-render GPU scaling to get to 100% from whatever the primary display at logon time was originally using.

@jphughan 

As a test, I disconnected the DP cable, and plugged in a HDMI, and lo and behold the desktop "bleed" was resolved. Obviously this is not an acceptable solution.  Any ideas?

@dan2021  Ok, the photo looks like the GPU is applying overscan to the display for some reason.  That's typically done for TVs, but maybe the driver is incorrectly identifying the display as a TV for some reason.  Somewhere in the Intel Graphics Control Panel / Command Center is a setting to control this, and I think the default is 90%, meaning the core 90% of the rendered content gets stretched out to the display area, cropping off the last 10%.  I don't remember exactly where it is, but I've seen it in there.  Set that to 100% and you should be able to see the full image.

Tried your suggestion, and no dice. See attached.

@jphughan 

@jphughan Is this something that can resolved in the NVIDIA 930MX GPU settings?

@dan2021  The NVIDIA settings would only come into play if the NVIDIA GPU had direct control of the video outputs, which I doubt it does.  When you have the displays configured so that one display appears normal the the other has overscan, if you go to Windows Display Settings > Advanced display settings, what is the active signal resolution shown for each of the displays, both the "normal" one and the one exhibiting overscan?  And then what resolutions do the displays themselves report receiving from the source system when you check their onscreen menus?

I'll see if I can grab a screenshot of the overscan control feature in Intel Graphics Command Center later, but I'm rather busy today.

The active signal resolution for display 1 is 3840x2160, 29 Hz

The active signlation resolution for display 2 is 1920 x 1080, 59 Hz (the overscan monitor)

However, when I go into general display settings, it shows both monitors at 1980 x 1080.  

Thanks.

@dan2021  Ok, well that's the issue.  Windows is rendering at 1920x1080 but the signal on the wire to one of the displays is still the display's native resolution of 3840x2160, and then only at 30 Hz.  There are some cases where maintaining the display's native resolution as your on-the-wire signal even when rendering at a lower resolution can be useful, but those do not include cases like this where the goal is to free up bandwidth.  I think Windows defaults to keeping the active signal resolution matched to the display's resolution whenever possible (which it wouldn't be for both of these displays simultaneously from a non-Thunderbolt system), but changing resolutions using the Intel Graphics app may force the active signal resolution to change rather than just the desktop (render) resolution.  You might have to switch the display to some other resolution and then back to 1080p using the Intel Graphics app to force the change given that the displays are already running a 1080p desktop resolution.

@dan2021  Open Intel Graphics Control Panel / Command Center, change the resolution to something else, and change it back to 1080p.  No you likely would not have to do that every time you switch laptops because Windows remembers display setups when a given set of physical displays are connected.

@jphughan 

"You might have to switch the display to some other resolution and then back to 1080p using the Intel Graphics app to force the change given that the displays are already running a 1080p desktop resolution."

How do I do that? And are you saying I will have to do this everytime I swap laptops? 

I am very close to giving up and just returning the monitors and dock.