Had this machine (specs lower down) for about two years. It came with dual AMD FirePro W4100 adapters, into which I plugged four monitors, two into each. As the cards have miniDP ports, and none of my cables had, I had to buy some adapters to use the monitors.
All was working fine until I had to reinstall Windows 7 a few months ago. After that, I would find that sometimes when I restarted, Windows would have rearranged some of my windows from their previous positions. As I have four monitors, this could be annoying, as I have my windows set up in specific places.
This got a bit worse, to the point where I rang Dell, who suggested that it was the miniDP adapters I was using that might be the problem. I bought four new cables, DP->miniDP, DVI-miniDP and VGA->miniDP as appropriate, and used those instead.
Instead of fixing the problem, it has become significantly worse. Now, every single time I lock my machine (fairly regularly, as I work from home and have small children), when I unlock, my windows are all over the place. When I say, I mean all over the place. Some are just on other monitors, some are across two monitors, some are partly off the screen and so on. They are fairly consistent in where they are (although not always), but pretty much every window gets moved.
It's now go to the stage where I can minimise and maximise a window, and have it moved form one monitor to another. At the moment, this only happens with two applications (Chrome and Microsoft SQL Server Management Studio), but it's really annoying.
Anyone able to help? The error message that pops up from time to time (not that often considering this happens every time I lock the screen) is unhelpful. It claims there is a problem with the connection between the computer and the DP display, but this seems unlikely, as why would both DP monitors fail at the same time, how come the problem wasn't fixed (and actually got worse) with new cables, how come all monitors (DP and otherwise) seem to work fine otherwise, and how come the windows are arranged over all monitors, not just the two DP ones?
The notification ends with "For more information" and that's it. No indication of where to go for more information.
I have checked the Windows event logs, and there is nothing in there that seems the slightest bit related.
Anyone able to help? Thanks.
PC: Dell Precision T5810
OS: Windows 7 Pro x64
CPU: Intel E5-1630 V3 @ 3.70GHz, 4 cores, 8 logical processors
Graphics Card(s): 2 x AMD FirePro W4100
Monitor(s) Displays: Asus PB279, Dell U2311H, AOC F22 & Dell E3211H
Screen Resolution: 1 at 2560x1440 and 3 at 1920x1080
Hard Drives: 1Tb Samsung 850 SSD, 1Tb Western Digital WD10EALX HDD, 6Tb Seagate external (USB)