Comment 24 for bug 1476343

Hi, Christopher. Thanks for all the helpful links! Indeed, I applied the BIOS update, and the hard freeze is now gone! It's not all working exactly as I expect, but at least the BIOS change cured the worst symptom.

Changes made:
Applied MSI BIOS update to version 71D.
Changed light-locker back to activate on screensaver activate.

New behavior when coming back to laptop with locked screen:
Make a movement on the touchpad. Screen remains completely black, BUT computer is still running properly, as shown by network traffic.
Click the mouse buttons. Same thing, screen remains completely black, but no hard crash; everything is still running.
Press some non-typing keys (shift, ctrl, etc.). Same thing.
Blindly type my password into the completely black screen. Screen turns on, unlocks, and shows me my full working X environment, exactly as I'd left it.

Which is at least usable. Not ideal, and not what I think is expected behavior, but behavior I can deal with.

chaz@cesium:~$ sudo dmidecode -s bios-version && sudo dmidecode -s bios-release-date
[sudo] password for chaz:
E1763IMS.71D
04/17/2015
chaz@cesium:~$