Timetec 8GB KIT(2x4GB) Compatible for Apple DDR3 1067MHz / 1066MHz PC3-8500 CL7 for Mac Book,
Install memory in an iMac - Apple Support
Amazon.com: Timetec 8GB KIT(2x4GB) Compatible for Apple DDR3L 1600MHz for Mac Book Pro (Early/Late 2011,Mid 2012), iMac(Mid 2011,Late 2012,Early/Late 2013,Late 2014,Mid 2015), Mac Mini(Mid 2011,Late 2012) MAC RAM : Electronics
CMS 6GB (1X4GB) & (1X2GB) DDR2 6400 800MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with Apple® iMac Core 2 Duo 2.4 20-Inch Early 2008 - B117 at Amazon.com
CMS 4GB (1X4GB) DDR2 6400 800MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with Apple® iMac Core 2 Duo 2.4 20-Inch Early 2008 - A42 at Amazon.com
CMS 6GB (1X4GB) & (1X2GB) DDR2 6400 800MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with Apple® iMac Core 2 Duo 2.4 20-Inch Early 2008 - B117 at Amazon.com
Install memory in an iMac - Apple Support
CMS 4GB (1X4GB) DDR2 6400 800MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with Apple® iMac Core 2 Duo 2.4 20-Inch Early 2008 - A42 at Amazon.com
Install memory in an iMac - Apple Support
4GB Kit (2GBX2) DDR2 800MHz RAM Memory Upgrade for Apple iMac Core 2 Duo 20-inch (Early 2008) (PARTS-QUICK) - Walmart.com