Windows 7 SP1, latest bios (A16) and drivers installed. In the power plan the hard drive is set to turn off Never and Display is set between 2 (testing) and 60 minutes (Default).
If connected to external displays and using the laptop screen when the devices is left inactive long enough for the display to turn off it will not resume from any keystroke or pressing the power button.
Closing and re-opening the lid has no effect, and verbal threats appear to be completely ignored so far. The computer must be forcibly rebooted and then it comes up fine. I've tested with multiple monitors, connecting via different cables: vga, dvi, and display port and all these setups experienced the problem.
When the laptop screen is not utilized as a display (lid shut) and only external monitors are used it resumes fine. I have several dozen users reporting the problem but I'm pretty sure all of our 250+ E6540s have the problem as a newly imaged machine exhibits it as well as the half dozen I randomly tested out in the wild did too (even though their user never complained).
Since this issue started up in the last 6 months and we've had a good number of these laptops for 2 years my next step will be re-building an image without all the windows updates and newer drivers then rolling it forward until I see the problem. Since that's going to take a lot of time and effort I wanted to get this post out first.
Thank you for your time and any suggestions are appreciated!