Apple iMac G5 (20-inch, iSight) vs Apple iMac (Retina 5K, 27-inch, 2019)

Every spec side by side, from each maker's published figures.

Better figure, where one is clearly better

iMac G5 (20-inch, iSight) compared with iMac (Retina 5K, 27-inch, 2019)
AppleiMac G5 (20-inch, iSight)AppleiMac (Retina 5K, 27-inch, 2019)
Overview
ReleasedOctober 2005March 2019
Performance
ProcessorIBM PowerPC G5 2.1 GHz (iMac iSight)Intel Core i5-8500, Intel Core i5-8600, Intel Core i9-9900K or Intel Core i5-9600K
CPU cores16 or 8
CPU threads–6 or 16
GraphicsATI Radeon X600 XT (128 MB DDR)Radeon Pro 570X (4 GB GDDR5), Radeon Pro 575X (4 GB GDDR5), Radeon Pro 580X (8 GB GDDR5) or Radeon Pro Vega 48 (8 GB HBM2)
Memory512 MB, 1 GB, 1.5 GB or 2.5 GB8 GB, 16 GB, 32 GB or 64 GB (better)
Storage250 GB to 500 GB256 GB to 3 TB (better)
CPU2.1 GHz PowerPC G5 with 512 KB L2 cache and 700 MHz frontside bus; single-core identity cross-checked with exact EveryMac source. Generic maker-clock chip record avoids borrowing uncertain silicon revision or unpublished thread/power figures.Six-core Core i5 at 3.0 GHz (Turbo Boost 4.1 GHz), 3.1 GHz (Turbo Boost 4.3 GHz) or 3.7 GHz (Turbo Boost 4.6 GHz); upper two bases configurable to 3.6 GHz eight-core Core i9 with Turbo Boost up to 5.0 GHz. Exact K-suffix CPU identities follow Geekbench’s model database; Macworld instead lists KF suffixes.
GPUATI Radeon X600 XT with 128 MB dedicated DDR video memory; PCI Express.Radeon Pro 570X or 575X with 4 GB GDDR5, or Radeon Pro 580X with 8 GB GDDR5; only the upper base supports Radeon Pro Vega 48 with 8 GB HBM2
Memory type533 MHz DDR2; 512 MB built in plus one expansion slot. Maker factory upgrades provide total capacities of 1, 1.5 or 2.5 GB.2666 MHz DDR4; 8 GB standard as two 4 GB modules in four user-accessible SO-DIMM slots. Lower base configurable to 16/32 GB; upper two bases to 16/32/64 GB.
Storage type250 GB 7200 rpm Serial ATA hard drive, configurable to 500 GB. Slot-loading 8x SuperDrive with 2.4x double-layer DVD writing, 4x DVD rewritable writing and 24x CD writing.570X base: 1/2 TB Fusion Drive or 256/512 GB/1 TB SSD. 575X base: 1/2/3 TB Fusion Drive or 256/512 GB/1 TB SSD. 580X/Vega base: 2/3 TB Fusion Drive or 512 GB/1/2 TB SSD.
Display
Screen size20″27″
Resolution1680 × 10505120 × 2880 (better)
Panel–IPS LCD
Brightness280 nits500 nits (better)
Display typeTFT active-matrix LCD with millions of colours; typical contrast 800:1 and viewing angles of 170 degrees horizontal and vertical. Panel technology and refresh rate unpublished.LED-backlit Retina 5K display; IPS panel confirmed by EveryMac; Apple does not publish native refresh rate in this model’s specification sheet
Display features–Wide colour (P3); supports one billion colours
Connections
Ports3 × USB-A, Ethernet, headphone jack2 × Thunderbolt 3, 4 × USB-A, SD card slot, Ethernet, headphone jack
Ethernet1 Gb/s1 Gb/s
External displays–Up to 2
Wi-Fi802.11g802.11ac
Bluetooth2.0 + EDR4.2
CameraiSight cameraFaceTime HD
Back portsThree USB 2.0 ports on the computer, plus two USB 1.1 ports on the keyboard; two FireWire 400 ports sharing 8 W, Mini-VGA output, Gigabit Ethernet, headphone/optical output and audio line-in.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 displaysOptional Mini-VGA adapters provide VGA mirroring or S-video/composite output; no DVI connector or extended-desktop mode is listed.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
CameraBuilt-in iSight; exact maker resolution is unpublished and omitted.–
SpeakersBuilt-in stereo speakers and microphone; 12 W digital amplifier.Stereo speakers
Microphones–Built-in microphone
Keyboard and mouseApple Keyboard, Mighty Mouse and Apple Remote.Rechargeable Magic Keyboard and Magic Mouse 2; optional Magic Keyboard with Numeric Keypad and Magic Trackpad 2
Design and power
TypeAll-in-oneAll-in-one
Weight10 kg9.42 kg (better)
Width × depth × height493 × 189 × 472 mm650 × 203 × 516 mm
Operating systemmacOSmacOS
Size and weight detailMaker reference weight; actual weight varies with configuration and manufacturing process.Dimensions include the stand; weight varies by configuration. A built-in VESA mount version was also available.
Power supplyMaximum continuous power 180 W; 100–240 V AC, 50–60 Hz.100–240 V AC, 50–60 Hz, single phase
Materials–Recyclable aluminium enclosure; arsenic-free glass and mercury-free LED backlight
In the boxiMac G5, Apple Keyboard, Mighty Mouse, Apple Remote, power cord, install/restore DVDs and documentation; Mac OS X Tiger, iLife ’05, Front Row and Photo Booth. Apple announced availability the week after 12 October 2005; release remains October at month precision.iMac, Magic Keyboard, Magic Mouse 2, power lead and Lightning to USB cable

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