http://bugs.winehq.org/show_bug.cgi?id=30954
--- Comment #5 from Dan Kegel dank@kegel.com 2012-06-20 16:02:33 CDT --- What does 'free -m' say right after boot, and every five minutes during gameplay?
You could run the script while free -m do date sleep 300 done > memory.log 2>&1 while running the game to find out.