Disable monitor detection for Windows 7

Many people know the problem you get when you use multiple monitors in combination with one or more KVM-switches on a Windows 7 system: As is so often the case with Microsoft stuff, Windows tries to be “smart” and it reacts to your switching the monitor by moving application windows from one screen to another.

If you search for this problem on the Internet, you find many solutions, including disabling some system services or changing a registry key DMMEnableDDCPolling to 0.

All lines connected 1:1 except pin 11I have taken a different approach to solve this: The monitor detection works via a dialogue between the computer and the monitor through one or two seperate lines in the VGA cable. So all we need to do is to take away that connection!

I have built a simple adapter plug with a 15-pin VGA connector on each side (one male, one female). 14 lines are simply connected right through, only the connection on pin 11 is left out. This is one of the data lines in the VGA connection.

The result is the PC is now blind to my switching the monitors. This makes switching between the monitors so much more convenient! Only disadvantage is the PC cannot autodetect the best screen resolution and refresh rate when starting up. You may need to select the appropriate screen resolution manually when you power up the PC (maybe once every day?) After that you can switch as often as you like (100x a day?) All your windows and icons stay right where you put them!


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