Now the consumer electronic devices screen more and more small, but the resolution is increased, such as Surface pro,10.6 inch screen, 1080p Full HD display, will make Windows display text becomes unusually small. This phenomenon is due to the fact that the screen dot pitch is smaller than the standard (about 207.82 dots per inch, the standard is about 96 dots per inch), but the display is more subtle, but the Windows rendering of text is still the default DPI (you can tell by the following that it is 96 dots per inch). So the text becomes smaller.
To make the text look less strenuous, our general practice is to magnify the DPI of the system. In fact, this is somewhat similar to the concept of PPI for digital image sampling, assuming that the Windows DPI is elevated to allow windows to have a higher sampling resolution for the UI elements, the Resampling UI elements get a larger number of pixels than the previous, longer and wider, on the same screen , it takes up more pixels than ever before, so the elements you see become larger.
But sometimes, in the event that we customize an too large DPI (for example, 500%), we can find that the system interface element becomes too large after the application and the login, so we can't go to the control Panel to find the setting and change it back by manipulating the UI. At this point we have a correct way to reboot into safe mode.
The DPI setting is user-related, that is, the DPI setting you do is only valid for your current user. Therefore, the DPI setting is also saved under the HKCU branch of the registry. A more secure method than direct manipulation of the registry is to reboot into Safe mode, then change the DPI settings back to normal, and then restart the computer. This is because the DPI zoom setting is not applied in safe mode and the size of all UI elements will return to normal.
Note that in the Advanced startup option, if you select Enable low-resolution video mode, the UI elements will be too large and will increase (because the resolution is lower). This pattern can be used to solve some of the problems with the graphics driver, but the DPI setting is not related to the graphics driver, so be careful to opt into safe mode to fix the problem.
If you also want to know where the DPI setting resides in the registry, take Win8 for example, which is located under the Hkey_current_usercontrol Paneldesktop project with the key named "Logpixels." By default, there is no such key or key value in the system, but if you set the DPI zoom, the key appears. By default, Windows's DPI absolute value is 96, but it is not visible through the DPI Setup interface. The corresponding relationship between the DPI setting and the registry key values is given here:
As you can see, the registry holds a key value that is the true DPI absolute value, and the percentage shown in the UI is based on the definition of "96 ' = ' 100%". So, after you manually adjust the DPI settings, you can easily work out the true DPI value. For devices like Surface Pro, the system has automatically set the default DPI to 150%.