Hm… update to this recent post of mine.

I just found this blog post about VMWare Fusion’s support for Snow Leopard. Hadn’t thought about that yet – it doesn’t support 64 bit as the host yet, and possible won’t do so for the foreseeable future. In that case, I can’t even use the 64 bit kernel, since VMWare support is very important for me. Well.

That makes me think a thought I’ve never thought before… never really wondered too much about 32 vs 64 bit on the Mac. Guess why? Because it doesn’t seem to be important. Why is it important on Windows? Simple: because you can’t have more than 3.something GB of RAM in your machine before it stops recognizing more RAM on 32 bit. So if my current Leopard installation is 32 bit, how come it works with the 16GB I have in my Mac Pro? As usual, there’s probably more to the 32 and 64 bit labels than you see at a glance… answers welcome – I may research myself, but not now :-)

Update: A quick Google search revealed the answers – everything’s right here. Interesting read. Short answer: Mac OS X, as well as Linux, can use PAE to make available more than 4GB even in 32 bit. For reasons better left unexplored here, Windows can’t.