Following the recent release of the OS X Mountain Lion Golden Master to developers, Apple has now officially clarified which Macs do and do not support the upcoming operating system.
From Apple’s Mountain Lion upgrade page:
Your Mac must be one of the following models:
- iMac (Mid 2007 or newer)
- MacBook (Late 2008 Aluminum, or Early 2009 or newer)
- MacBook Pro (Mid/Late 2007 or newer)
- MacBook Air (Late 2008 or newer)
- Mac mini (Early 2009 or newer)
- Mac Pro (Early 2008 or newer)
- Xserve (Early 2009)
These requirements have been known for a while, but now that Apple has released the GM, and has confirmed the compatibility list with a posting of their own, it’s worth taking note of. The reason Mountain Lion doesn’t support some older 64-bit Macs is likely due to driver support for the graphics chips installed in those machines.
If you’re planning on updating, make sure your machine supports it first! Don’t worry – if you forget, the Mac App Store will remind you!