Apple iMac (20-inch, Mid 2009) 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 (20-inch, Mid 2009) compared with iMac (Retina 5K, 27-inch, 2019)
AppleiMac (20-inch, Mid 2009)AppleiMac (Retina 5K, 27-inch, 2019)
Overview
ReleasedApril 2009March 2019
Performance
ProcessorIntel Core 2 Duo 2 GHz (iMac Mid 2009) or Intel Core 2 Duo 2.26 GHz (iMac Mid 2009)Intel Core i5-8500, Intel Core i5-8600, Intel Core i9-9900K or Intel Core i5-9600K
CPU cores26 or 8
CPU threads–6 or 16
GraphicsNVIDIA GeForce 9400M (256 MB shared DDR3)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)
Memory1 GB, 2 GB or 4 GB8 GB, 16 GB, 32 GB or 64 GB (better)
Storage160 GB to 320 GB256 GB to 3 TB (better)
CPU2.0 or 2.26 GHz Core 2 Duo with 3 MB shared L2 cache and 1066 MHz frontside bus. The retained configuration table says 2.6 GHz, but its processor description and Apple's July 2011 education price list confirm 2.26 GHz; exact Intel SKU not established.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.
GPUNVIDIA GeForce 9400M with 256 MB shared DDR3 according to the retained maker specification; contemporary EveryMac coverage describes 128 MB at launch, so the retained maker value is used.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 typeTwo SO-DIMM slots for 1066 MHz DDR3; configurations A/B have 1 GB standard and C has 2 GB. Factory options are 2 or 4 GB; the retained specification supports up to 8 GB, which is not listed as a factory configuration.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 type160 or 320 GB 7200 rpm Serial ATA hard drive; slot-loading 8x SuperDrive with 4x double-layer DVD burning.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
Brightness290 nits500 nits (better)
Display typeGlossy TFT active-matrix LCD with millions of colours; typical contrast 800:1 and 160-degree horizontal and vertical viewing angles. 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
Ports4 × USB-A, Ethernet, headphone jack2 × Thunderbolt 3, 4 × USB-A, SD card slot, Ethernet, headphone jack
Ethernet1 Gb/s1 Gb/s
External displaysUp to 1Up to 2 (better)
Wi-Fi802.11n draft802.11ac
Bluetooth–4.2
CameraiSight cameraFaceTime HD
Back portsFour USB 2.0 ports on the computer, plus two on the keyboard; FireWire 800 at 7 W, Mini DisplayPort, Gigabit Ethernet, headphone/optical digital output and line-in/optical digital input. Bluetooth is not published in this exact model specification.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 displaysBuilt-in display and one external display up to 2560 × 1600 simultaneously; extended desktop or mirroring, with optional DVI, VGA or dual-link DVI adapters.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
SpeakersBuilt-in stereo speakers and microphone; internal 24 W digital amplifier and support for Apple Stereo Headset microphones.Stereo speakers
Microphones–Built-in microphone
Keyboard and mouseApple Keyboard and Mighty Mouse.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
Weight9.1 kg (better)9.42 kg
Width × depth × height485 × 189 × 469 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 200 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 boxEducation institution model. Contemporary EveryMac coverage records April 2009 release; a maker-confirmed first delivery day is unavailable. Launch configuration A includes Leopard and iLife ’09; later B/C specifications list Snow Leopard and iLife ’11, with their introduction dates unestablished.iMac, Magic Keyboard, Magic Mouse 2, power lead and Lightning to USB cable

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