Windows 7 moves/resizes windows on monitor power cycle

I had the same problem symptoms, also on a 2560x1440 monitor. In my case it was on the Fujitsu T904. It worked fine until I upgraded to Windows 10, then I started having this problem -- windows shrink and move to upper left when computer goes to sleep.

I had high hopes, but unfortunately, the Simulated... key had the correct 2560 and 1440 values. There were other monitors inside the Configuration section with values of 1024x768 and 1280x1024, but changing those had no effect.

It seems to be a function of the setting for "Change the size of text, apps, and other items:" If I set this to 200% (default), then there is no change when it goes to sleep. And if I set it all the way down to 100%, that's when I see the biggest size change.

I also notice when it first awakes from sleep that the lock screen image does not fill the monitor window. It's as if that screen is still at the original 200%, and that changes over before the system goes to sleep to change my display, but then it switches back when I unlock.

I hope this added description helps someone diagnose and solve...

A long lived thread :)

I had the same problem and fortunately the registry fix did the trick.

My computer is running windows 10 pro and I had numerous registry entries at HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\GraphicsDrivers\Configuration because I used different monitors to test which one was best for my needs.

I finally decided to use my ASUS PB287Q UHD 4K monitor so I deleted all entries and reboot, only one entry was created using the correct screen resolution (3840x2160) to recreate the 'simulated' reg entry I went to display settings and used the "change the size of text, apps and other items: blah% (recommended)" option and changed it.

Now that the simulated entry is there I changed the resolution in four places.

1. Under key 00, PrimSurfSize.cx and cy
2. Under key 00,00 PrimSurfSize.cx and cy
3. Under key 00,00 ActiveSize.cx and cy

and last. Since the following entries had the incorrect resolution 1024x768 I decided to change them anyway.

4. Under key 00,00 DwmClipBox.right and DwmClipBox.bottom

I want to thank all of the posters for helping me solve the problem.

PS I haven't tested this but I assume that going to display settings and changing the "change the size of text, apps and other items: blah% (recommended)" option will overwrite or create additional "simulated" reg entries so you might have to modify the registry each time you change this option.

Wow ... I found this discussion thread after encountering the re-sizing issue on my new 4K monitor.  It is startling to see the discussion has been going on for five years, with over 26,000 "views" and no response from Microsoft ... whew!

Anyway, I thought I would share a "work-around" that helped me.  I have an LG 4K monitor (31MU97-B) with a Gigabyte GeForce GTX970 graphics card (driver 355.82) and I am running Windows 7.  I setup the monitor with the DisplayPort and soon encountered the re-sizing issue.  Changing the configurations in the registry, as suggested by others, did not work for me.  It was mentioned that DisplayPort is seen as a PnP device that disconnects from the computer when the monitor is put into sleep mode.  So, I decided to make a secondary connection to the monitor through HDMI.  I still need the DisplayPort connection to get the resolution and refresh rate, but now with an HDMI connection the computer and graphics card do not disconnect when the monitor is put to sleep.  I suppose a secondary DVI connection might work similarly, but my monitor only has DP and HDMI inputs so I could not test this possibility. Windows shows my resolution as 4096x2160, which is the native resolution of monitor and it detects the HDMI connection as "monitor 2."  The "multiple displays" are set to "Extend these displays."

I use the small utility called "NirCmd" (http://www.nirsoft.net/utils/nircmd.html) to turn the monitor off.  So far, so good ... no re-sizing of windows or changing of resolutions.

It seems to me that DisplayPort is the problem in my case and as long as I use a secondary input through HDMI the computer does not get "confused" when DP disconnects.

Just want to add my complaint for the record - I am still struggling to get 2560x1440 to work on two different computers, one DVI, one DP.

I am using Windows 10, deleted all the Configuration entries in the Registry and re-started. Two entries were created,

MS_00033_00_07D2_68^053F0EFEF06B4081A061218DDBD8A55E

  > 00

       > 00

NVT78C521573_01_07DC_93^D3B7C0A20BF5F02821F15BA821D1CE17

  > 00

       > 00

My motherboard seems to have a 1024x768 embedded display support which I assume relates to the first entry. The second entry has the correct numbers for my 2560x1440 monitor connected by DVI. I have never seen a "SIMULATED" entry that people have discussed on this board.

Overall behavior is very frustrating. If I sleep from the Start Menu, then resume from the front panel power switch (but making sure the monitor itself is resumed first), the desktop layout is correct. So something at a basic level does work!

But typically, if the computer sleeps on timeout, or if the monitor is asleep when the computer resumes, bad things happen.