Apple iMac (21.5-inch, Late 2015) vs Apple iMac (Retina 5K, 27-inch, Late 2015)

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iMac (21.5-inch, Late 2015) compared with iMac (Retina 5K, 27-inch, Late 2015)

	AppleiMac (21.5-inch, Late 2015)	AppleiMac (Retina 5K, 27-inch, Late 2015)
Overview
Released
Released	October 2015	October 2015
Performance
Processor
Processor	Intel Core i5-5250U or Intel Core i5-5575R	Intel Core i5-6500, Intel Core i7-6700K or Intel Core i5-6600
CPU cores
CPU cores	2 or 4	4
CPU threads
CPU threads	–	4 or 8
Graphics
Graphics	Intel HD Graphics 6000 or Intel Iris Pro Graphics 6200	AMD Radeon R9 M380 (2 GB GDDR5), AMD Radeon R9 M390 (2 GB GDDR5), AMD Radeon R9 M395 (2 GB GDDR5) or AMD Radeon R9 M395X (4 GB GDDR5)
Memory
Memory	8 GB or 16 GB	8 GB, 16 GB or 32 GB (better)
Storage
Storage	256 GB to 2 TB	256 GB to 3 TB (better)
CPU
CPU	1.6 GHz dual-core Core i5 with Turbo Boost up to 2.7 GHz or 2.8 GHz quad-core Core i5 with Turbo Boost up to 3.3 GHz; Geekbench identifies the processors as Core i5-5250U and Core i5-5575R, respectively	3.2 GHz quad-core Core i5 with Turbo Boost up to 3.6 GHz in the M380 and M390 models; 3.3 GHz quad-core Core i5 with Turbo Boost up to 3.9 GHz in the M395 model. Only the M390 and M395 bases support the 4.0 GHz Core i7 upgrade, with Turbo Boost up to 4.2 GHz.
GPU
GPU	Intel HD Graphics 6000 in the 1.6 GHz model and Intel Iris Pro Graphics 6200 in the 2.8 GHz model; no discrete graphics option	AMD Radeon R9 M380 or M390 with 2 GB GDDR5; M395 with 2 GB GDDR5 in the upper base, configurable to M395X with 4 GB GDDR5 only in that base
Memory type
Memory type	8 GB of 1867 MHz LPDDR3 onboard memory, configurable to 16 GB; soldered memory cannot be upgraded after purchase (Expert Reviews and Alphr)	1867 MHz DDR3; 8 GB standard as two 4 GB modules, configurable to 16 GB or 32 GB; four user-accessible SO-DIMM slots
Storage type
Storage type	1 TB 5400-rpm hard drive on both models; the 1.6 GHz model can have a 1 TB Fusion Drive or 256 GB SSD, and the 2.8 GHz model can have a 1 TB or 2 TB Fusion Drive or 256 GB SSD. Apple specifies 24 GB of flash for the 1 TB Fusion Drive and 128 GB for the 2 TB Fusion Drive.	M380 base: 1 TB 7200-rpm hard drive, 1/2/3 TB Fusion Drive or 256/512 GB SSD. M390 base: 1/2/3 TB Fusion Drive or 256/512 GB/1 TB SSD. M395 base: 2/3 TB Fusion Drive or 256/512 GB/1 TB SSD. The 1 TB Fusion Drive has 24 GB of flash; 2/3 TB Fusion Drives have 128 GB.
Display
Screen size
Screen size	21.5″	27″
Resolution
Resolution	1920 × 1080	5120 × 2880 (better)
Panel
Panel	IPS LCD	IPS LCD
Display type
Display type	21.5-inch LED-backlit display with IPS technology; 1920 × 1080 with support for millions of colours. This is the non-Retina model.	LED-backlit Retina 5K display with IPS technology and support for millions of colours
Display features
Display features	–	P3 colour gamut; Apple does not publish brightness or refresh rate in this model's specification sheet
Connections
Ports
Ports	2 × Thunderbolt 2, 4 × USB-A, SD card slot, Ethernet, headphone jack	2 × Thunderbolt 2, 4 × USB-A, SD card slot, Ethernet, headphone jack
Ethernet
Ethernet	1 Gb/s	1 Gb/s
External displays
External displays	Up to 1	Up to 2 (better)
Wi-Fi
Wi-Fi	802.11ac	802.11ac
Bluetooth
Bluetooth	4.0	4.0
Camera
Camera	FaceTime HD	FaceTime HD
Back ports
Back ports	Four USB 3 ports, two Thunderbolt 2 ports with Mini DisplayPort output, SDXC card slot, Gigabit Ethernet, headphone and optical digital audio output; Kensington lock slot. HDMI, DVI, VGA and dual-link DVI need separately sold adapters.	Four USB 3 ports, two Thunderbolt 2 ports with Mini DisplayPort output, SDXC card slot, Gigabit Ethernet, 3.5 mm headphone and optical digital audio output; Kensington lock slot. HDMI, DVI, VGA and dual-link DVI require separately sold adapters.
External displays
External displays	Built-in display at native resolution alongside one external display up to 3840 × 2160 on the 1.6 GHz model or 4096 × 2304 on the 2.8 GHz model; extended desktop and video mirroring	Built-in display at full native resolution alongside up to two 4096 × 2160 displays, or one 5120 × 2880 dual-cable display; extended desktop and video mirroring
Speakers
Speakers	Stereo speakers; supports Apple iPhone headset with microphone	Stereo speakers; supports Apple iPhone headset with microphone
Microphones
Microphones	Dual microphones	Dual microphones
Keyboard and mouse
Keyboard and mouse	Magic Keyboard, Magic Mouse 2 and Lightning to USB cable; optional Magic Trackpad 2	Rechargeable Magic Keyboard and Magic Mouse 2; optional Magic Trackpad 2 with Force Touch
Design and power
Type
Type	All-in-one	All-in-one
Weight
Weight	5.68 kg (better)	9.54 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, but its listed height in inches conflicts with the metric value and is omitted.	Dimensions include the stand; weight varies by configuration. 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 11.5 dB at idle and during wireless web, and 12 dB during hard-drive seek, tested on the 1.6 GHz Core i5 with 8 GB memory and 1 TB hard drive	Apple's 3.3 GHz Core i5, 8 GB, 2 TB Fusion Drive and Radeon M395 test configuration: operator-position sound pressure 15.5 dB at idle, wireless web and hard-drive seek
Materials
Materials	Recyclable aluminium enclosure; arsenic-free display glass and mercury-free LED backlight; speaker enclosures contain 35 percent post-consumer recycled plastic	Recyclable aluminium enclosure; arsenic-free display glass; mercury-free LED backlight
In the box
In the box	iMac, Magic Keyboard, Magic Mouse 2, Lightning to USB cable and power lead; OS X El Capitan at launch. The support sheet's macOS Sierra wording reflects a later software update.	iMac, Magic Keyboard, Magic Mouse 2, power lead and Lightning to USB cable