Apple iMac (27-inch, unibody, 2009) review: Apple iMac (27-inch, unibody, 2009) - CNET
8GB Kit (4GBx2) Upgrade for a Apple iMac 2.66GHz Intel Core 2 Duo (20-inch - DDR3) MB417LL/A System (DDR3 PC3-8500, Non-ECC, ) at Amazon.com
How I kept my iMac running for a decade | Cult of Mac
Apple iMac Core i5 i7 27" Late 2009 Logic Board MB953LL/A A1312 820-27 - Part Haven
8GB -2x4GB Memory Ram Upgrade 20" Apple iMac 9.1 2.66GHz Core 2 Duo Early 2009 | eBay
Someone gave me this unwanted Mac, anyone know if you can upgrade the graphics cards on these ? Keep seeing conflicting information it's a 24" early 2009 imac : r/mac
2009 Mac Pro CPU Replacement (quad-core) - iFixit Repair Guide
Late-2009 Mac Mini Socketed CPU Upgrade - YouTube
iMac 21.5" Late 2009 (10,1) - CPU Upgrade E8600 | MacRumors Forums