Windows 7 moves/resizes windows on monitor power cycle

I gave up on a fix so my workaround is as follows

1. Disable sleep and hibernate. Disable put monitor to sleep
2. Every night shutdown PC
3. Start PC in the morning
4. Launch apps and setup windows where I want them
5. Use PC all day (with monitors always powered on)
6. Back to #2 at night

So I'm probably shortening the life of my monitors and using some extra power.  Not sure what it costs to run two 27" Dell displays for 12 hours a day but it can't be too bad.   

Just couldn't take coming back to PC after an hour and every window was on one screen, overlapping each other and all icons rearranged.  

Microsoft should have already fixed this.  I don't think 20 pages here shows this is an edge case and there are other threads on this on Microsoft website as well as other tech forums.  C'mon Satya!  Get your team of developers to fix this.  Build a patch or just a tool to repair it.

I'm replying to myself here: I had initially reported this hack to be the solution but after months of using it I found it to be a half solution. Windows still move around when monitors are turned off. Specially annoying is that also window number assignments are also moved around so programs that are set to open windows on monitor #n suddenly need a re-configuration.

Out of frustration I have developed the following morning ritual to wake up my pc: unplug all dp and hdmi cables, turn monitors on, plug cables back in the order I want the monitors assigned numbers, wait a few seconds for windows to do its 'magic', then start a tedious process of re-arranging the windows, having to close and re-open any programs that had a 3d accelerated view on because those don't survive the turning-off process.

I too have the same sort of problems and there are many parallels, 2 x 4K screens (iiyama), Nvidia GTX970 video card, DisplayPort connections, Windows 7. I have windows that move between screens, or completely disappear, even though they show as running, you can't get to them.

As the BIOS screen output only seems to reliably come out on the HDMI I have also got the HDMI on the graphics card to the primary screen so I can manually flip to this if I need to. This screen was set to disabled in Windows display config.

I tried the SIMULATED key fix, but it didn't work for me. I tried 2560x1440 (one screen) and 5120 x 1440 with stride of 20480 (4 x 5120) - representing two screens. After several reboots still no joy.

After backing up the GraphicsDrivers registry keys, I removed all the configuration and connectivity keys and rebooted. I also reinstalled the latest NVidia drivers.

Windows hasn't as yet re-create the SIMULATED key or NOEDID key, but it has created a bunch of different configurations (6 so far), this seems to relate to which monitor powers up first. You can make it generate more by powering off different monitors in different orders or pulling the cables from the video card, etc

My problem is now far better, but not completely fixed as some windows still move, but the off-screen window issue seems to be less of a problem now.

I also tried the 2 x DP and disconnecting the HDMI, plus the duplicating the DP to the HDMI as one screen (which is a neat trick that I'd missed before !). HDMI only didn't fix it either.

I have also found that you can get to hidden application windows that are off-screen by hovering over the icon on the task bar, waiting for the mini icon of the window to pop up above it, then move up to the mini window, right click and select move. Now press any arrow key on the keyboard, then move the mouse and you have the window attached to the mouse. You can now place it back on  the screen.

I agree with everyone else that this should have been fixed now, after all if we are supposed to be doing our bit to save power, then things should work properly so that users are not inconvenienced.

I'm new to Windows10.  

The idea that I can't effectively use my 3 monitors is making me rather upset.  It's this sort of problem that gives MS a bad rap.  As this thread is testament, it's been a bug for years.  Everytime my system go to sleep, I end up having to readjust all the windows on my editing software.  

Why?

No good reason as far as I can see.

Anyway, the "solution" involves doing a hack on something called the registry file.  What is that and how do I even access it?  It looks like a bunch of nonsense to me.  Plus, there's no guarantee it works anyway. 

More important, why do I have to mess with it at all?  I'm a layperson not a computer scientist for goodness sake.  Why should I be poking around entering strings and code into a file I don't understand?

Auuugh.