The optional Upgrades for the Apple iMac 27 are not worth it - NotebookCheck.net News
Placa base Original probada 820 3299 A 820 3478 A 820 3481 A 820 00134 A para iMac 27 "A1419 placa lógica 2012 2013 2014 2015 Año|Pantalla LCD de portátil| - AliExpress
27-inch imac cpu upgrade? | MacRumors Forums
Upgrade iMac Intel Core i3 CPU to Core i7 - iFixit Repair Guide
A Pragmatist's Opinions: 2011 iMac Upgrade
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iMac (Late 2015) CPU Upgrade from i5 to i7 6700K. (sped up) - YouTube
Apple iMac 27" CPU Upgrade Prozessor Austausch i7 i9 4 bis 8 Core CPU Service | eBay
Upgrade processor iMac (mid 2010 specifically) - Ask Different
The CPU Selection - The 27-inch Apple iMac Review (2011)