Memory Upgrades for iMac 27-Inch (2012 - Mid 2015)
How to Upgrade the RAM in Your iMac
Apple iMac Mid 2007 Intel Core 2 Duo (2017 Review) - YouTube
A-Tech for Apple 6GB Kit (1x2GB + 1x4GB) DDR2 667MHz PC2-5300 200-pin SODIMM for MacBook (Late 2007, Early 2008, Early 2009), MacBook Pro (Mid 2007, Early 2008), iMac (Mid 2007) - Memory RAM Upgrade at Amazon.com
iMac Intel 20" Mid 2007 EMC 2133 - used original spareparts for Macs