iMac 2009 to 2011 (A1311/A1312) Upgrade Guide – MacintoshMen
ssd - What are my hardware upgrade options for a late 2009 iMac? - Ask Different
Late 2009 iMac 27" Video Card Repair — 4850 — 2nd Bake - YouTube
iMac | 3.06 GHz Core 2 Duo | 21.5 Inch | Late 2009 - Techable.com
For Apple iMac 21.5" A1311 Mid/Late 2009 2010 2011 NVIDIA K1100M 2GB Video Card | eBay
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iMac 2009 to 2011 (A1311/A1312) Upgrade Guide – MacintoshMen