2013 iMac teardowns reveal SSD slots, soldered-in CPU in the 21.5” model | Ars Technica
Apple iMac 21.5" Late 2013 A1418 Logic Board i5 2.9GHz 5200 1GB 1GB 66 | MacKing
iMac RAM upgrade: Here's an affordable way to improve multitasking - CNET
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