Nvidia K1100M upgrade on the Mid-2010 iMac 21.5' 

This video will show a process on how to replace and upgrade GPU on iMacs from 2009, 2010 and 2011. In this video, our GPU candidate will be a workstation card from Nvidia. This method should apply on any iMac from 2009 to 2011. However, this method might not work on 2009 iMacs that Core2Duo LGA 775 socket. Make sure it has one of intel core i3, i5 or i7 series.
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