When you use a high-DPI device such as a Surface Pro 3, Surface Pro 4, or Surface Book together with external monitors, you experience the following issues:
Elements such as applications, the taskbar, icons, toolbars, text, and dialog boxes appear to be fuzzy.
Elements are too large or too small compared to the rest of the desktop.
Blurry text appears in applications or in the Windows interface.
Although these symptoms may be seen on a single monitor, they're more common when you use multiple monitors that vary in display resolution. These symptoms also occur when the hardware configuration changes, such as when you dock and undock a device that uses external monitors, or you detach an external monitor from the device.
These issues commonly occur in the following scenarios:
Applications are moved between monitors that use different display resolutions.
The monitor that applications are displayed on changes between docked and undocked configurations.
Users mix connections during the same logon session. For example, users log on through a remote desktop connection (RDC), and later connect directly without first logging off.
Display information is determined when a user logs on to the system. A logoff-logon process resets the display information and improves behavior. However, the issue recurs if the monitor configuration changes during the same logon session, such as when you dock or undock the device or detach an external monitor.
This issue has become more prevalent since the introduction of 4k and higher resolution monitors, especially when these monitors are mixed together with older, standard monitors.
For more information about how Windows scales applications, see the following Core Team Blog articles:
Improvements are continuously being added to Windows 10 and Office 2016 applications. If you are experiencing a specific issue, first check whether it has been resolved in the latest Windows release or cumulative update. To check Windows 10 updates, see the following Microsoft Knowledge Base article:
Consider deploying monitors that have complementary screen resolutions.
When you use multiple monitors (including when you dock or connect to remote screens), a greater difference in the resolution between the native device and external device is more likely to cause the issues to occur. For more information, see the following OneDrive presentation:
Use or deploy Universal Windows Platform (UWP) applications instead of Win32 applications.
Modern (UWP) apps always scale correctly. If there is a comparable modern app available, you can substitute that app to mitigate the scaling issues. For example, Edge is a modern app that does not cause the DPI Scaling issues that Internet Explorer might experience. Similarly, Remote Desktop is an alternative to mstsc.exe.
Check for known issues
See the following articles for more information about known issues in these specific products.
In Process Explorer, click the columns, and then add the DPI Awareness column to the view.
Start the application that you want to check.
In Process Explorer, locate the application, and then examine the DPI Awareness column.
DPI Awareness status definitions
Per-Monitor Aware: Per-monitor DPI-aware. These applications check for the DPI when they are started, and adjusts the scale factor whenever the DPI value changes. These applications are not automatically scaled by the system.
System Aware: System DPI-aware. These applications do not scale for DPI changes. They query for the DPI one time, and then use that value for the lifetime of the application. If the DPI changes, the application does not adjust to the new DPI value. It will be automatically scaled up or down by the system when the DPI changes from the system value.
Unaware: DPI-unaware. These applications do not scale for DPI changes. They are always assumed to have a scale factor of 100 percent (96 DPI). These applications are automatically scaled by the system at any other DPI settings.
For more information, see the following MSDN topic:
Many UI elements have been updated because of customer feedback. Because DPI Scaling issues can involve multiple symptoms and configuration, information from users can help us identify specific scenarios and prioritize the development of updates.
To provide such feedback, follow these steps:
Record monitor configurations. To do this, take a screenshot of Display window (Start > Settings > System > Display).
For each monitor, note the make and model, scaling percentage, and resolution.
Record the steps that you must follow to reproduce the issue.
Take screenshots or video of the desktop or applications before and after the scaling issues occur.
Run DXDiag.exe on the system.
Select Start > Feedback Hub. Search on “DPI” to check whether any listed issue matches your specific issue. If you find a match, you can add additional feedback, including screen shots, DXDiag results, and any other relevant information.
Display scaling is a deceptively complex problem. There is no magic bullet or single fix to resolve all DPI Scaling problems. DPI Scaling benefits from continuous improvements in the core operating system, in application development models, and in applications from both Microsoft and third parties.
Different versions of Windows and application development models have different display scaling capabilities and limitations.
For example, the Windows 8.1 desktop environment and applications understand only one scale factor, generally based on the primary display at the time that the logon session starts. When the display changes in the middle of a logon session, the system bitmaps scale content from the system scale factor to the new monitor scale factor. This makes sure that content doesn’t become excessively large or small. However, text may appear blurred. (The effect is worse when you scale up.) If the system shrinks or stretches UI elements to the correct size, this may cause some blurriness in dialog boxes and other UI elements.
In Windows 10, investments were made so that large parts of the desktop UX will scale crisply in docking-undocking scenarios. Additional scalability improvements were made to the taskbar, File Explorer, desktop icons, context menu, and other UI elements to improve the user experience.
Microsoft is continuously updating the system and first-party applications. Third-party applications may require similar investments.