Home Desktops Apple iMac G4 (20-inch, USB 2.0) Apple · iMac
iMac G4 (20-inch, USB 2.0) Released November 2003
A PowerPC all-in-one with a large adjustable 20-inch display, DVD writer and compact dome-shaped base.
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Type All-in-one
Processor Motorola PowerPC G4 1.25 GHz (iMac USB 2.0)
Memory 256 MB – 1 GB
Storage 80 GB – 160 GB
Screen 20″
Weight 18.2 kg
Processor Motorola PowerPC G4 1.25 GHz (iMac USB 2.0)
CPU cores 1
Graphics NVIDIA GeForce FX 5200 Ultra (64 MB)
Memory 256 MB, 512 MB or 1 GB
Storage 80 GB to 160 GB
CPU 1.25 GHz PowerPC G4 with 167 MHz system bus and 256 KB on-chip L2 cache. Generic maker-clock record retains the single-core identity cross-checked with the exact EveryMac source; uncertain silicon revision is not inferred.
GPU NVIDIA GeForce FX 5200 Ultra with 64 MB dedicated DDR video memory and AGP 4x support.
Memory type 256 MB PC2700 (333 MHz) DDR SDRAM standard; factory options 512 MB or 1 GB. One 184-pin DIMM and one user-accessible SO-DIMM slot. Configurations retain Apple's supported 1 GB maximum, not unofficial upgrade limits.
Storage type 80 GB 7200 rpm Ultra ATA/100 hard drive, configurable to 160 GB; 4x SuperDrive DVD-R/CD-RW. Published memory and storage factory options are retained for the 1.25 GHz processor. Display
Screen size 20″
Resolution 1680 × 1050
Brightness 230 nits
Display type Widescreen TFT active-matrix LCD with millions of colours and typical 350:1 contrast. Panel technology and refresh rate are not published in the exact maker sheet.
Display features Typical viewing angles: 170° horizontal and vertical; articulated display arm adjusts height and angle. Connections
Ports 3 × USB-A, Ethernet, headphone jack
Ethernet 0.1 Gb/s
Back ports Three USB 2.0 ports on the computer, up to 480 Mbps, plus two USB 1.1 ports on the keyboard; two FireWire 400 ports with 8 W shared power, Mini-VGA, 10/100BASE-T Ethernet, 56K V.92 modem, headphone jack, Apple speaker minijack and audio line-in. AirPort Extreme 802.11g card and internal Bluetooth are optional, rather than standard.
External displays Mini-VGA provides video mirroring on a VGA display or S-video/composite television through optional adapters. Output resolutions: 640 × 480 at 60 Hz, 800 × 600 at 75 Hz or 1024 × 768 at 75 Hz.
Camera The external iSight shown in the product image is an optional accessory; this iMac has no integrated camera.
Speakers Built-in speaker and microphone, Apple Pro Speakers rated at 7 W each and internal 14 W amplifier.
Keyboard and mouse Apple Keyboard, Apple Mouse, Apple Pro Speakers and modem cable. Wireless Keyboard and Wireless Mouse were optional accessories. Design and power
Type All-in-one
Weight 18.2 kg
Operating system macOS
Size and weight detail Adjustable maker ranges: height 354–530 mm, width 440–514 mm and depth 270–440 mm; base diameter 270 mm. Reference weight varies by configuration and manufacturing process.
Power supply 90–264 V AC, 47–63 Hz, single phase; maximum continuous power 190 W.
In the box Mac OS X 10.3 Panther and iLife, with Apple's productivity software and Tony Hawk's Pro Skater 4. Maker launch confirms immediate availability on 18 November 2003. Configurations Processor Memory Storage Storage type Graphics Motorola PowerPC G4 1.25 GHz (iMac USB 2.0) 256 MB 80 GB Hard drive NVIDIA GeForce FX 5200 Ultra (64 MB) Motorola PowerPC G4 1.25 GHz (iMac USB 2.0) 256 MB 160 GB Hard drive NVIDIA GeForce FX 5200 Ultra (64 MB) Motorola PowerPC G4 1.25 GHz (iMac USB 2.0) 512 MB 80 GB Hard drive NVIDIA GeForce FX 5200 Ultra (64 MB) Motorola PowerPC G4 1.25 GHz (iMac USB 2.0) 512 MB 160 GB Hard drive NVIDIA GeForce FX 5200 Ultra (64 MB) Motorola PowerPC G4 1.25 GHz (iMac USB 2.0) 1 GB 80 GB Hard drive NVIDIA GeForce FX 5200 Ultra (64 MB) Motorola PowerPC G4 1.25 GHz (iMac USB 2.0) 1 GB 160 GB Hard drive NVIDIA GeForce FX 5200 Ultra (64 MB)
Pros and cons Pros + Adjustable widescreen display+ Dedicated graphics memory+ USB 2.0 and FireWire connectivityCons − Single-core processor− Wireless networking requires an optional card− Video output mirrors the built-in displayNewer model: iMac G5 (20-inch, 2004) .
