Chances are, you’re already salivating to download the latest version of OS X 10.8, Mountain Lion, when it’s released later this summer. For a fair number of Mac owners, though, installing Mountain Lion is going to require buying a new machine, as Apple has abandoned support for Intel’s GMA 950 and x3100 chipsets.

Here’s a list of the machines that can run Lion that can’t run Mountain Lion :

Although OS X Lion has a minimum spec requirement of an Intel Core 2 Duo processor, Mountain Lion’s heftier graphics requirements effectively puts these machines to pasture:

• Any Intel Core 2 Duo MacBook from late 2007 – late 2008 (Model Numbers: MB061*/B, MB062*/B, MB063*/B, MB402*/A MB403*/A MB404*/A, MB402*/B)
• The Mid-2007 Mac mini (Model Numbers: MB138*/A, MB139*/A)
• Late 2006 polycarbonate iMac (Model Number: MA710xx/A)
• The original early 2008 MacBook Air (Model Number: MB003LL/A)

If you’ve got any one of these machines, OS X Lion will be the last version of OS X you will be able to install.

Source : cultofmac