THIS AUCTION IS FOR A 3.46GHZ 12-CORE CPU TRAY - THIS WILL WORK WITH ANY 2009 2010 OR 2012 4,1 OR 5,1 MAC PRO WESTMERE OR NEHALEM TOWER - NO CORE RETURN REQUIRED Before I ship I will need you to send me a photograph of the about this Mac page so that I can confirm your model year, I also will need to see confirmation of your system firmware. If your system has 4,1 firmware then I will need to assist with updating it to 5,1 before shipping.
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