Amazon.com: Timetec 8GB KIT(2x4GB) Compatible for Apple DDR3 1333MHz PC3-10600 for Mac Book Pro (Early/Late 2011 13/15/17 inch), iMac (Mid 2010, Mid/Late 2011 21.5/27 inch), Mac Mini(Mid 2011) RAM Upgrade : Electronics
Is it worth it to upgrade RAM on Mid 2010 21.5 iMac? | MacRumors Forums