KVM switch + Windows 7 creates monitor switching nightmare

Here are some more observations from my configuration. I'm beginning to think the disconnected-connected problem has nothing to do with EDID.

My monitor has a VGA cable and is connected to the video card with a DVI to VGA adapter. If I unplug just the VGA cable, regardless of going through the KVM switch or not and regardless of the EDID override, I don't hear the disconnected-connected sound. Only if I unplug/replug both the cable and the adapter at the same time I get the sounds. Again the KVM switch or the override do not make any difference, so that would indicate the "connected" status is not based on the EDID.

If I first unplug just the VGA cable, and then the adapter, I get the disconnected sound, but if I then replug just the adapter, and then the VGA cable I don't get any sound at all. The DVI to VGA adapter has the hot plug pin 16 permanently wired to the +5V pin 14, so the hot plug pin is definitely involved.

I did some googling and found comments that indicate the connected status is determined by the hot plug pin, and detecting load on the signal pins, not the EDID. That would explain why I consistently get the connected-disconnected sound only if the unplug/replug both the adapter and the cable at the same time, regardless of the EDID-stripping KVM.

So, perhaps some monitors are making the inputs temporarily float when you turn on the power. If you are then using a DVI cable, the combination could make the overly anxious W7 think the monitor is temporarily unplugged. I have no idea what could possibly make it happen if the monitor is already on. In any case, using a VGA cable might help as a workaround since the DVI to VGA adapter makes sure the hot plug pin is always "hot".

Xenubite,

Thanks for the ideas.  Since I have Windows set to "Show desktop only on 2", it isn't actually in clone mode, so that's not the problem.  Extended mode isn't what I want either, since I keep the notebook lid closed and dark, and I don't want any windows to open themselves on the internal display (although I did test extended mode, and the problem remained).

I opened the lid for a few minutes in "Show desktop only on 2" mode, and sure enough, whenever the KVM monitor goes black for a few seconds, the internal display lights up for the same period.  Not sure that it's the internal display "waking up" though.  I think the external display is momentarily "getting lost", since Windows makes the "device disconnect" sound when the KVM monitor goes black and "device reconnect" when it returns.

Worse yet, I got a blue screen after I re-closed the lid; not immediately, but a few minutes later.  After closing the lid, Windows 7 no longer saw the internal display (which seemed to temporarily fix the problem actually), but then it suddenly gave me the BSOD.

I just have to shake my head that Microsoft would do this to us in Windows 7 ... the supposed solution to the Vista disaster.  Arrgh.  I have now wasted *hours* trying to find a fix because Microsoft broke something that has worked for *years*.

When was the last time someone remotely related to MS posted anything on here? I fear they will wait to see of this will die out by itself... instead of fixing the frackin' problem!

Well sorry to say this but the EDID_OVERRIDE registry hack which was working for me, suddenly stopped working! :(

what is strange to me is that based on what i see in the registry, i shouldnt even be having the problem. I have two devices in the Display key. One is my Dell 2408WFP and the other is called KVM2004, both have identical EDID information, identical resolutions etc. yet when i switch away from that system it is now always resizing and repositioning all my windows because it has reverted to some LOW resolution whilst i was away!

This problem and YES I DO CALL IT A PROBLEM, is so annoying, i fear i may need to fall back to Vista since i have a GPT partition and XP will not work. 

This really sux!

EDIT: Well i discovered that for some reason the VNC 'fix' which had been somewhat of a workaround, had somehow during one of my KVM switches away, reverted to a resolution of 1024x768.  Using VNC i set the resolution to 1920x1200 and all is well with me again. Why it reverted however is a mystery and i am sure part and parcel of the problem MS has thrown into the laps of thousands of KVM users along with a recommendation we go purchase switches which are compatible with their Operating System.  Yes i know this is not only a KVM issue, but in my case it is and i want a REAL fix.

Well it seems Microsoft is getting record O/S sales with Windows 7, so it looks like the disatisfaction of the minority here isn't worth the minimal PR it would take for a tech to drop by and say

"Hey, I see the problems you guys are having. It's not top of our list but we want to get this sorted out, please bear with us while we research the problem."

or something similar to indicate the problem is acknowledged and in need of a solution to appease us.

Kind of disssapointing that a problem as plain as day as this can't penetrate the Microsoft machine - even with all the Microsoft support staff frequenting here.

They know about it and don't know how to fix it without violating DRM contracts.  Remember who we are dealing with here.  IP protection far outweighs usability.