CPU Performance - 21.5-inch iMac (Late 2013) Review: Iris Pro Driving an Accurate Display
OWC SSD Upgrade Kits For Mac Pro Cylinder 2013
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Amazon.com: OWC 2TB Aura Pro X2 NVMe SSD Upgrade Kit Compatible with Select 27" and 21.5" iMac Models (Late 2013 - Current) : Electronics
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Apple iMac 21.5-inch and 27-inch (Late 2013) reviews | Macworld
Apple iMac
Amazon.com: INDMEM 512GB NVMe PCIe SSD 3D TLC NAND Flash Hard Drive Disk 512G Only for Late 2013 - Mid 2015 MacBook Pro, Mid 2013-2017 MacBook Air, Late 2013-2017 iMac, Late 2013
HOW I UPGRADED MY iMAC 21.5in Late 2013 MODEL (SSD & RAM UPGRADE) - YouTube