|Originally Posted by RandomEmpire
Hey guys, I had the same problem with you with Steam crashing on my Mac. I've discovered that the issue is a memory leak on the Store page that causes crashes at around 3GB. The cause appears to be the banner/slider showing the 48 hour game deals.
To avoid the crashing you simply do not load the Store page in the same session as gaming. By default the Store page is the first thing that will load once Steam has opened, and that causes the problem. To prevent the Store page from loading go to Steam Preferences and click the "INTERFACE" tab. The second dropdown box should be your "Favorite window" option. Change it to "Library", then click "OK". Now relaunch Steam. Steam will open and your games Library will load up. Now you should be able to game without Steam crashing! Provided you don't load the Store page, if you want to view the Store in Steam make sure you relaunch it before gaming.
Spread this around as it's solved the problem for me and I no longer detect a memory leak. I know myself and another have both had no crashes since doing what I said above.