I am using iMAC 11,1 current os version is 10.6.8 and Processor 2.66 Ghz Intel Core i5 with 4 GB of DDR3 RAM with this configuration Can I install OS 10.8.4 ?
Excellent user tip for upgrading to Mountain Lion > Mountain Lion 10.8 Updating requirements
If your model number is 11.1, you can install it if you have 8GB free disk space.
If you can install 10.8.4, here is another good user tip about how to do it.
Install Mountain Lion Successfully from 10.6.8
I would also recommend making an installer, which Kappy covers.
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