I have a MacBook with Retina display, and I experience some of these screen resolution issues in my Windows virtual machine:
- Windows screen resolution is low - the screen looks blurry.
- Windows icons are very small or very large.
- Windows screen resolution is very high - everything looks tiny.
- I have an external display connected to my portable Mac computer.
Windows and other operating systems are not adapted for such high pixel density (DPI). Learn more about the MacBook Pro Retina display in this Apple article: Frequently asked questions about using a Retina display.
Parallels Desktop provides enhanced Retina display support for Windows 7 and Windows 8 virtual machines.
In the Mac menu go to Actions (the Virtual Machine menu in older versions of Parallels Desktop) -> Configure... -> Hardware -> Video to see Resolution options for your virtual machine.
How to solve display issues on a MacBook Pro with Retina display:
Note: The Resolution settings shown in the images below apply to Windows 7 and Windows 8 virtual machines. Resolution options are different for Windows XP and Windows Vista virtual machines.
To learn how to change DPI scaling in Windows, see this article from Microsoft: Make the text on your screen larger or smaller.
Troubleshooting: Windows image is blurry or scaled
Troubleshooting: Windows resolution is too high
Troubleshooting: Windows Fonts and icons are too big or too small
Troubleshooting: Unreal screen resolution on external display with black borders (on main screen everything looks correctly):
In the Mac menu go to Actions (the Virtual Machine menu in older versions of Parallels Desktop) -> Configure... -> Hardware -> Video -> Disable Retina support
Windows 7 resolution in full screen with Retina display as a primary monitor is doubled on the secondary display and the picture is down-scaling. It is "by design" because Windows 7 does not support secondary monitors with doubled DPI. If Parallels Desktop would not set the force down-scaling, it would be worse. So the workaround is leave the current settings, where Retina is disabled in the VM's config.
Windows 7 draws the background picture on the 2nd monitor based on the size of the background on the primary monitor. If the secondary monitor resolution is higher than the primary has, the background picture will be the same as you have provided to us. This is how Windows works. To remove black borders in this case, you need to:
- Right click on the desktop anywhere -> click Personalization -> Desktop Background -> Picture Position and choose "Center". With this preference there should not be any black borders on the 2nd monitor.