I have a 2011 i7 with 6970 2GB, 24Gb RAM, and factory SSD. I used to crash in Lions Arch around large groups and sometimes as I approached waypoints in the world. Actually made me quit playing for a long period of time because I didn’t like playing in Parallels (but there were no crashes in Win7)..
To the point, a thread floating around on these forums for people with our exact rigs mentioned setting graphics to low, and I haven’t crashed a single since, which was 5 months ago. My graphics were on some form of Custom setting by default.
The hypothesis is some effect that isn’t rendering properly with the AMD gpu through the cider wrapper and causes the boot, which sounds similar to yours.