This has happened to me 5 times in a row now.
What I'm doing: I load a saved game where I am near rivacheg. I immediately engage battle with some pirates to the east a little (assuming the ocean is south). The pirates are already battling a vaegir caravan so I'm just helping the vaegirs out.
Once in battle, I tell the one riding unit to dismount then i tell them all to hold position.
I ride around and kill a few pirates and then it crashes. When it crashes, it either crashes to a black screen and my computer freezes, crashes to the desktop and restarts, or simply restarts. Most of the time it just crashes to a black screen and freezes.
This has happened while I was in the middle of battling pirates, while I was standing still on a hill looking down on the pirates, while I was riding towards the pirates, and while I just entered the battle.
I didn't have any crash problems before the .61 update. I had a couple assertion errors, but nothing more.
Intel Pentium 1.7 GHz
512 MB of Ram
Video card:
ATI Radeon 9600 (mobile)
This is a laptop I'm running it on.