I updated to the latest last week, maybe it's that? But it did crash two times before with a gap of a few months, before it did 3 times in the last week.
I thought that could be that, for a few years I've had something sat on the computer which covered part of the air vents. I've moved it now, but maybe it started to cause overheating I'll clean the inside & see if things improve.
It only crashes during a game, so I'm lucky in that sense that it doesn't stop my save working.