Apple iMac G3 (Revision B) vs Apple iMac (Retina 4K, 21.5-inch, 2019)

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iMac G3 (Revision B) compared with iMac (Retina 4K, 21.5-inch, 2019)

	AppleiMac G3 (Revision B)	AppleiMac (Retina 4K, 21.5-inch, 2019)
Overview
Released
Released	October 1998	March 2019
Performance
Processor
Processor	PowerPC G3 233 MHz (iMac)	Intel Core i3-8100, Intel Core i7-8700 or Intel Core i5-8500
CPU cores
CPU cores	1	4 or 6
CPU threads
CPU threads	–	4, 6 or 12
Graphics
Graphics	ATI RAGE Pro (6 MB)	Radeon Pro 555X (2 GB GDDR5), Radeon Pro 560X (4 GB GDDR5) or Radeon Pro Vega 20 (4 GB HBM2)
Memory
Memory	32 MB or 256 MB	8 GB, 16 GB or 32 GB (better)
Storage
Storage	4 GB	256 GB to 1 TB (better)
CPU
CPU	233 MHz PowerPC G3 with 66 MHz system bus and 512 KB backside L2 cache. The generic chip record names no supplier; MacGeneration identifies a Motorola PowerPC 750 in its reviewed Revision B unit.	3.6 GHz quad-core Core i3 without Turbo Boost, or 3.0 GHz six-core Core i5 with Turbo Boost up to 4.1 GHz; both configurable to 3.2 GHz six-core Core i7 with Turbo Boost up to 4.6 GHz
GPU
GPU	ATI RAGE Pro graphics with 6 MB video memory; Apple’s developer history confirms the graphics change from the original RAGE IIc model.	Radeon Pro 555X with 2 GB GDDR5 in the lower base; Radeon Pro 560X with 4 GB GDDR5 in the upper base, configurable to Radeon Pro Vega 20 with 4 GB HBM2
Memory type
Memory type	32 MB SDRAM standard, two SO-DIMM slots. Current retained Apple Revision B sheet supports up to 256 MB; the older developer history gives 128 MB. Configurations use the current maximum, with the conflict recorded.	8 GB standard, configurable to 16/32 GB; lower base uses 2400 MHz DDR4 and upper base 2666 MHz DDR4. Memory is not readily user-accessible.
Storage type
Storage type	4 GB IDE hard drive and tray-loading 24x CD-ROM.	The current Apple sheet lists 256 GB SSD or 1 TB Fusion Drive for both bases, and these are the configurations shown. Apple made SSD storage standard in August 2020. Launch reviews describe a 1 TB hard drive in the lower base and 1 TB Fusion Drive in the upper base, with larger SSD options (Macworld and TechRadar); these historical options are not flattened into the current matrix.
Display
Screen size
Screen size	15″	21.5″
Resolution
Resolution	1024 × 768	4096 × 2304 (better)
Panel
Panel	–	IPS LCD
Brightness
Brightness	–	500 nits
Refresh rate
Refresh rate	75 Hz	–
Display type
Display type	Nominal 15-inch CRT, 13.8-inch viewable diagonal; no fixed LCD native resolution.	LED-backlit Retina 4K display; IPS panel confirmed by EveryMac; Apple does not publish native refresh rate in this model’s specification sheet
Display features
Display features	1024 × 768 at 75 Hz, 800 × 600 at 95 Hz and 640 × 480 at 117 Hz (EveryMac exact A/B specification).	Wide colour (P3); supports one billion colours
Connections
Ports
Ports	2 × USB-A, Ethernet, 2 × headphone jack	2 × Thunderbolt 3, 4 × USB-A, SD card slot, Ethernet, headphone jack
Ethernet
Ethernet	0.1 Gb/s	1 Gb/s (better)
External displays
External displays	–	Up to 2
Wi-Fi
Wi-Fi	–	802.11ac
Bluetooth
Bluetooth	–	4.2
Camera
Camera	–	FaceTime HD
Back ports
Back ports	Two USB ports, 10/100BASE-T Ethernet, 56K modem and audio line-in/out, plus two front headphone jacks. The retained combined maker sheet lists IrDA; Apple’s developer comparison lists it only for the original revision, while MacGeneration’s physical Revision B review shows the infrared window. No standard FireWire or VGA output.	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; SDXC, Gigabit Ethernet and 3.5 mm headphone jack; Kensington lock slot. Thunderbolt 2, HDMI, DVI and VGA require separately sold adapters.
External displays
External displays	–	Built-in display at full 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
Speakers
Speakers	Built-in stereo speakers and microphone.	Stereo speakers
Microphones
Microphones	–	Built-in microphone
Keyboard and mouse
Keyboard and mouse	Apple USB Keyboard and round Apple USB Mouse.	Rechargeable Magic Keyboard and Magic Mouse 2; optional Magic Keyboard with Numeric Keypad and Magic Trackpad 2
Design and power
Type
Type	All-in-one	All-in-one
Weight
Weight	–	5.48 kg
Width × depth × height
Width × depth × height	–	528 × 175 × 450 mm
Operating system
Operating system	macOS	macOS
Size and weight detail
Size and weight detail	Maker retained sheet gives height 15.8, width 15.2 and depth 17.6 inches, weight 40 pounds. Metric figures from the original revision are not borrowed.	Dimensions include the stand; current Apple sheet lists 5.48 kg and warns that weight varies by configuration. Launch reviews tested heavier hard-drive/Fusion configurations. A built-in VESA mount version was also available.
Power supply
Power supply	–	100–240 V AC, 50–60 Hz, single phase
Materials
Materials	–	Recyclable aluminium enclosure; arsenic-free glass and mercury-free LED backlight
In the box
In the box	Mac OS 8.5. Conservative October 1998 sale month follows MacGeneration’s exact Revision B retrospective; published introduction days differ and are not treated as a verified worldwide first-sale day.	iMac, Magic Keyboard, Magic Mouse 2, power lead and Lightning to USB cable