Apple iMac (21.5-inch, 2017) vs Apple iMac (Retina 5K, 27-inch, 2020)

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iMac (21.5-inch, 2017) compared with iMac (Retina 5K, 27-inch, 2020)

	AppleiMac (21.5-inch, 2017)	AppleiMac (Retina 5K, 27-inch, 2020)
Overview
Released
Released	June 2017	August 2020
Performance
Processor
Processor	Intel Core i5-7360U	Intel Core i5-10500, Intel Core i5-10600, Intel Core i9-10910 or Intel Core i7-10700K
CPU cores
CPU cores	2	6, 8 or 10
CPU threads
CPU threads	4	12, 16 or 20
Graphics
Graphics	Intel Iris Plus Graphics 640	Radeon Pro 5300 (4 GB GDDR6), Radeon Pro 5500 XT (8 GB GDDR6), Radeon Pro 5700 (8 GB GDDR6) or Radeon Pro 5700 XT (16 GB GDDR6)
Memory
Memory	8 GB or 16 GB	8 GB, 16 GB, 32 GB, 64 GB or 128 GB (better)
Storage
Storage	256 GB to 1 TB	256 GB to 8 TB (better)
CPU
CPU	2.3 GHz dual-core Intel Core i5 with Turbo Boost up to 3.6 GHz; Geekbench identifies the exact processor as Core i5-7360U	Six-core Core i5 at 3.1 GHz (Turbo Boost 4.5 GHz) or 3.3 GHz (4.8 GHz), or eight-core Core i7 at 3.8 GHz (5.0 GHz). Upper two bases configurable to 3.6 GHz ten-core Core i9 (5.0 GHz). Exact CPU identities follow Geekbench. Apple specifies a 5.0 GHz Core i7 limit in this iMac, while Intel lists 5.1 GHz for the chip itself.
GPU
GPU	Intel Iris Plus Graphics 640; no discrete graphics option	Radeon Pro 5300 with 4 GB GDDR6 on the two Core i5 bases. Upper base has Radeon Pro 5500 XT with 8 GB GDDR6, optionally Radeon Pro 5700 with 8 GB or 5700 XT with 16 GB GDDR6.
Memory type
Memory type	8 GB of 2133 MHz DDR4, configurable to 16 GB	2666 MHz DDR4; 8 GB standard as two 4 GB modules. Four user-accessible SO-DIMM slots; configurable to 16/32/64/128 GB on every base.
Storage type
Storage type	1 TB 5400-rpm hard drive, configurable to 1 TB Fusion Drive or 256 GB SSD	Lower base: fixed 256 GB SSD. Middle base: 512 GB/1/2 TB SSD. Upper base: 512 GB/1/2/4/8 TB SSD.
Display
Screen size
Screen size	21.5″	27″
Resolution
Resolution	1920 × 1080	5120 × 2880 (better)
Panel
Panel	–	IPS LCD
Brightness
Brightness	–	500 nits
Display type
Display type	21.5-inch LED-backlit display; 1920 × 1080 with support for millions of colours. Apple does not identify the panel technology, native refresh rate or brightness in its specification sheet; Retina model display figures do not apply.	LED-backlit Retina 5K display; IPS panel confirmed by EveryMac. Apple does not publish native refresh rate in the specification sheet.
Display features
Display features	–	Wide colour (P3), one billion colours and True Tone; standard glass or optional nano-texture glass
Connections
Ports
Ports	2 × Thunderbolt 3, 4 × USB-A, SD card slot, Ethernet, headphone jack	2 × Thunderbolt 3, 4 × USB-A, SD card slot, Ethernet, headphone jack
Ethernet
Ethernet	1 Gb/s	1 Gb/s
External displays
External displays	Up to 2	Up to 2
Wi-Fi
Wi-Fi	802.11ac	802.11ac
Bluetooth
Bluetooth	4.2	5.0
Camera
Camera	FaceTime HD	1080p FaceTime HD
Back ports
Back ports	Four USB-A ports, two Thunderbolt 3 (USB-C) ports, SDXC card slot, Gigabit Ethernet, 3.5 mm headphone jack and Kensington lock slot. Thunderbolt 3 supports DisplayPort, up to 40 Gb/s Thunderbolt and up to 10 Gb/s USB 3.1 Gen 2; Thunderbolt 2, HDMI, DVI and VGA require adapters.	Four USB-A ports; two Thunderbolt 3 USB-C ports with DisplayPort, Thunderbolt up to 40 Gb/s and USB 3.1 Gen 2 up to 10 Gb/s; UHS-II SDXC, Gigabit Ethernet and 3.5 mm headphone jack; Kensington lock slot. Optional 10Gb Ethernet supports 1/2.5/5/10Gb connections. Thunderbolt 2, HDMI, DVI and VGA require adapters.
External displays
External displays	Built-in display at native resolution alongside one 5120 × 2880 display at 60 Hz with one billion colours, two 3840 × 2160 displays at 60 Hz with one billion colours, or two 4096 × 2304 displays at 60 Hz with millions of colours	One 6K or 5K external display, or two 4K displays; two 6K displays require Radeon Pro 5700 or 5700 XT. All listed external modes run at 60 Hz.
Speakers
Speakers	Stereo speakers; supports Apple iPhone headset with microphone	Stereo speakers
Microphones
Microphones	Built-in microphone	Three-mic array with directional beamforming; supports Hey Siri
Keyboard and mouse
Keyboard and mouse	Magic Keyboard, Magic Mouse, Lightning to USB cable and polishing cloth; configurable with Magic Keyboard with Numeric Keypad or Magic Trackpad	Rechargeable Magic Keyboard and Magic Mouse 2; optional numeric keyboard and Magic Trackpad
Design and power
Type
Type	All-in-one	All-in-one
Weight
Weight	5.44 kg (better)	8.92 kg
Width × depth × height
Width × depth × height	528 × 175 × 450 mm	650 × 203 × 516 mm
Operating system
Operating system	macOS	macOS
Size and weight detail
Size and weight detail	Dimensions include the stand; weight varies by configuration and manufacturing process. A built-in VESA mount version was available.	Dimensions include the stand; weight varies by configuration and manufacturing process. A built-in VESA mount version was also available.
Power supply
Power supply	100–240 V AC, 50–60 Hz, single phase	100–240 V AC, 50–60 Hz, single phase
Noise
Noise	Apple reports operator-position sound pressure of 11 dB at idle and during wireless web, and 12 dB during hard-drive seek, tested on the Core i5 with 8 GB memory and 1 TB hard drive	–
Materials
Materials	Aluminium enclosure; arsenic-free display glass; mercury-, BFR- and beryllium-free with regional exceptions for PVC-free power leads	Recyclable, low-carbon aluminium enclosure; arsenic-free glass and mercury-free LED backlight
In the box
In the box	iMac, Magic Keyboard, Magic Mouse, Lightning to USB cable, polishing cloth and power lead. Apple's current support page describes the later macOS Big Sur release.	iMac, Magic Keyboard, Magic Mouse 2, power lead, Lightning to USB cable and polishing cloth