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I Have 4GB Of RAM and I have the 2GHZ Intel Core 2 Duo. I was wondering what is the highest CPU I can upgrade to.
The best drop in supported CPU was the Intel Core Duo X7900 which can be found for $20 - $50 but the Intel Core Duo T7800 is also supported and can normally found cheaper. If you want you can fiddle with newer operating systems you will have to get a T9300 or T9500 but there have been issues reported. More can be found in this link- replacing X7900 to T9300 for macOS Sierra install Is it worth it?
