This is probably the most painful issue I have with Windows 10 right now (and likely previous versions as well, but I didn't have a multi-monitor setup back then).
The monitors I have are as follows:
- 3840x2160 (4K UHD) monitor with preferred DPI: 144 (150%)
- 1920x1080 (Full HD) monitor with preferred DPI: 96 (100%)
Whenever one of these monitors are set as primary, all desktop applications displayed on the secondary monitor (doesn't matter which) has blurry text. Exceptions are the Windows Store Apps like Windows Store and Microsoft Edge, along with the Taskbar/Start Menu, the Taskbar/Start Menu settings screen, the Taskbar context menu, and the desktop context menu which passes the DPI test with flying colours, with crispy text on both monitors (occasionally a DPI switch bug gets in, but I can mostly ignore that). The problem is, as you can probably guess, is that >99% of the applications I use aren't Windows Store Apps.
Here are some screenshots. The "Taskbar and Start Menu Properties" text is what the text should look like while the Visual Studio 2015 text is an example of the text most desktop apps get. The blurry image is what happens when the UHD monitor is not the primary monitor.
Attachment 48493Attachment 48494
Note: Both of these screenshots came from the 150% DPI monitor so it's best viewed at that (144) DPI level. The 96 DPI monitor is similarly affected.
Things I've already tried:
- Reinstall the graphics driver (this was unhelpfully given by a Microsoft Support Engineer). Did this multiple times in fact for unrelated reasons.
- Reinstall Windows 10 (through Reset This PC recovery option). I did this for also unrelated reasons but it definitely doesn't fix this issue.
- Use the XP Explorer "fix". Merely worsens the problem.
- Adjusting ClearType options. Alleviates the issue a bit but see next point.
- Disabling ClearType on the affected monitor. The text obviously sharpens, but it's painful to read and a close inspection of the text reveals the issue isn't solved at all, only mitigated slightly.
- Replacing the video card. I swapped this in with my older GTX 560 Ti but it's obvious the problem remains. Both it and my current card are NVIDIAs though, so it's vaguely possible the drivers or the cards themselves are the cause. I don't have an ATI/AMD card (that still works, at least) to test the setup and every Intel iGPU I have either has only one monitor output or is incapable of handling UHD resolutions.
Things I won't try:
- Setting both monitors' DPI to 96. Text would become microscopic considering the UHD monitor's actual size.
- Use the text resizing feature instead. I'm going take a wild guess that this is not monitor-specific and would cause everything on the HD monitor to be far too large to the point that I'd rather unplug it.
Does anyone have a multi-resolution, multi-DPI, multi-monitor setup with or without this issue? The text is painful to read on whichever is the secondary monitor right now, and is extremely apparent whenever the background is dark.