In order to be able to change the pixel density on Windows 7 and Windows Vista Service Pack 2, users will need devices with screens of at least 600 pixels in height. According to Microsoft, DPI Scaling will not work on computers on which the display resolution is lower than 600 pixels vertical.
The Redmond company explained that Vista SP1 and RTM were also impacted by this. However, the software giant revealed that the issue was by design, and that no hotfix, or resolve would be provided to end users.
“When you change system DPI Scaling from “Control Panel > Personalization > Adjust font size (DPI)” on Windows Vista, or from “Control Panel > Display” on Windows 7, you may notice that the displayed font size does not change,” the Redmond company stated. “When the DPI Scaling change is requested by user, the system will check to see if the screen height is over 600 pixels. This is done to reduce the chance that dialogs and other user interface elements become inaccessible due to lack of screen real estate.”
Users will need to look for devices with vertical screen resolutions of at least 600 pixels in order to be able to change the pixel density. Pixel density is a combination of the screen resolution and the actual physical screen size, and DPI stands for dots per inch, with Windows Vista and Windows 7 using a system of pixels per inch. The rule is that the higher the density of pixels, the higher the amount of detail on the screen. This is especially helpful for netbooks and other small devices that come with small screens.
“On Windows Vista using display resolutions that are lower than 600 pixels in height, the system will ignore the change request and will keep the DPI Scaling at a value that would continue providing useful dialogs and screens,” Microsoft added. “On Windows 7 in a similar situation, the user interface will inform the user that they can’t change the DPI scaling with the current screen resolution.”