The 2007 iMac 7,1 is compatible if the CPU is upgraded to a Penryn-based Core 2 Duo, such as a T9300. Early-2008 or newer Xserve (Xserve 2,1, Xserve 3,1) Early-2009 or newer Mac Mini or white MacBook (Macmini 3,1, MacBook 5,2) Late-2008 or newer MacBook Air or Aluminum Unibody MacBook (MacBookAir 2,1, MacBook 5,1) It is reported to work on theses unsupported machines: Here's the patch tool by dosdude for High Sierra, Iused his former patch to do the Sierra upgrade.

I did open a new install of MS Office 2011 which had reports that it was not going to work but so far have seen no issues. I did my first install of 10.13 last night on a 2012 13' MBP without issue as expected but really have not looks at it yet.

I posted this to see if anyone has done it yet, also because I know we will have question on it, and to see if anyone has attempted it yet and has any advice. I'm first going to try the install on a 2008 MacPro, then try it on either a 2008 and/or early 2009 MacBook Pro. But, after watching a couple of videos, right now it appears I will not have to do a firmware update.

At the time I did it last year, it appeared that it couldn't be done on the 2008 MacPro. I did the Sierra upgrade on a couple of MacPros 4,1 and it has worked excellently, after I did a firmware update patch to get it to read as a MacPro 5,1, so I am very optimistic on doing it again. I am currently researching installing OS X 10.13 High Sierra on unsupported Macs.

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