Not really sure if this is in the correct section. Basically my mac often struggles for ram, if i am browsing with a fair few tabs it is usually at 70-73% RAM. I've never seen it go higher even when it freezes due to low memory or when Safari pages all refresh due to low memory. (Or when I have to kill 'Safari Web Content'). I thought this was because it is 32bit but I read that the same doesn't exactly apply to OSX. So why does it never go above 75%?