Have the same problem from time to time. I use a GTX 780 with the latest drivers.
In my case it happens like this:
During a MWO match the screen freezes and everything looks like the computer has hung up. But thats not the case. Just MWO has stopped. Then I hit CTRL+ALT+DEL to get to the task manager and there I just have to click on the MWO task. Then I get back to the game immidiately and everything is fine.
During my time of absence my Mech runs straight ahead with the last speed he had. Sometimes when I'm not fast enough I get into a couple of enemys and then Im dead, but if no one is near by, I can switch back without an issue.
Edited by Desintegrator, 17 June 2014 - 08:02 AM.