Is it possible to install Mountain Lion on a Mac mini that is older than 2009, despite the system requirements?
you are lucky, this is mountain lion compatibility list
Mac mini Core 2 Duo with Nvidia graphics of 2009 and later
MacBook Core 2 Duo unibody of 2008 and later
MacBook Pro Core 2 Duo of 2007 and later
MacBook Air Core 2 Duo with Nvidia graphics 2008 and later
iMac of 2007 and later
Mac Pro of 2008 and later
Xserve Xeon Nehalem de principios de 2009.
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