KVM switch + Windows 7 creates monitor switching nightmare

This is all wild speculation, but perhaps with some monitors W7 is unable to get the EDID from a directly connected monitor when the monitor is off. I think the monitor is suppose to use the +5V power provided by the video card to power the system that returns the EDID, but because the earlier operating systems didn't constantly poll the EDID, they may have forgotten that part.

That would make W7 think an off monitor is unplugged, and would cause the desktop to shuffle every time you power off a monitor in a multiple monitor system, even when the monitors are connected without any KVM switches.

If that is the case the fix could be using the EDID override within each monitor. So instead of copying anything to Default_Monitor, since there most likely even isn't one, the EDID_OVERRIDE should be added to each monitor that already has a valid EDID in "Device Parameters", and the monitor's own EDID would just be duplicated in the EDID override. That should then make W7 think the monitor is always either on, or off but still plugged.

The underlying issue appears to be effecting people running mutliple monitors and in some cases it looks like even people running single monitors. So i think it goes a bit beyond the KVM user base. That this thread has more attention than the others may be a problem for getting microsofts attention though.

Since this mostly affects people using KVM switches MS does not endorse, there may not ever be a really elegant solution to it. I'm only hoping for a registry flag I could set to disable constant monitor configuration polling, so that I could set up the monitors once without the KVM switch, freeze the configuration, and then have that configuration stick no matter how I plug the cables. To refresh the configuration I would have to go to Control Panel display settings and click "Detect". Which I think is basically how XP worked.

My guess is the motivation for the constant monitor polling and ultra conservative settings when there is no EDID is to make it very hard for us to screw up and end up in a situation where there is no picture on the screen. A noble goal, but in this case it had pretty severe side effects.

Looks like it's a usable workaround.. we'll see what side effects come into play with driver updates etc, monitor configurations, if any.

I hope Microsoft is at least listening and puts some simple support into the O/S to allow disabling of this functionality soon.

I'll make mention of it in the other two threads related to problems caused by EDID.

The solution presented by Xenubite, as others have also stated, does work for me. While it may not be an official or authorized 'fix' assuming Microsoft even deems a 'fix' is necessary, given their seeming lack of positive information in this thread, this 'fix' is a good enough solution for me.  I will continue to monitor this thread for further developments, but not daily as i used to do.  Many thanks Xenubite for not only finding this solution but also for posting it here for others to take advantage of.