20″ iMac G5 (iSight)

Innovation has come back to the iMac. Just as the original iMac introduced USB to the Macintosh and eliminated the floppy drive, the October 2005 iMac G5 introduces the PCI-Express bus for video, DDR2 memory, and an integrated iSight webcam while eliminating the internal modem.

20" iMac G5 (iSight)Apple took the popular iMac G5, built in iSight, made it thinner and lighter, boosted speed by 100 MHz, and gave it a remote control. Throw in ATI Radeon X600 graphics on a PCI-Express bus and Apple’s Mighty Mouse, and you’ve got the Late 2005 iMac G5.

As with the May 2005 revision, Bluetooth and AirPort Extreme are standard features. There is no internal modem; it has been replaced by an optional external USB modem.

Who would have expected so many changes in the five months since the last revision?

Is there anything to be disappointed about? The only thing that seems to be missing is FireWire 800, which Apple still reserves for its “pro” models.

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  • introduced 2005.10.12 at US$1,699; reduced to US$1,499 2006.01.31; replaced by Intel Core Duo-based iMac 2006.01.10
  • requires Mac OS X 10.4.2 Tiger through 10.5 Leopard
  • CPU: 2.1 GHz G5
  • Bus: 700 MHz
  • Performance:
    • Geekbench 2 (Leopard): 1112
    • Geekbench 2 (Tiger): 1233
  • RAM: 512 MB, expandable to 2.5 GB using a single PC2-4200 DDR2 SDRAM
  • Graphics: ATI Radeon X600 XT with PCI-Express support
  • Display: 20″ 1680 x 1050 flat panel display
  • Video out: VGA, S-video (requires adapter)
  • L2 cache: 512 KB on CPU
  • Hard drive bus: 1.5 Mbps SATA I
  • Hard drive: 250 GB 7200 rpm SATA drive
  • Optical drive bus: UltraATA
  • SuperDrive: writes DVD±R discs at up to 8x speed, dual layer at up to 2.4x; DVD±RW at up to 4x; reads DVDs at up to 8x, writes CD-R discs at up to 24x, writes CD-RW discs at up to 8x, reads CDs at up to 24x
  • USB: 3 USB 2.0 ports
  • FireWire 400: 2 ports
  • Modem: optional 56 kbps USB modem supports v.92
  • Ethernet: 10/100/gigabit
  • WiFi: 802.11g AirPort Extreme included
  • Bluetooth: included
  • IR receiver: supports Apple Remote (included)
  • Microphone: internal
  • Power supply: 180W
  • H x W x D: 18.6 x 19.4 x 7.4 in/47.2 x 49.3 x 18.9 cm
  • Weight: 22 lb/10 kg
  • Part no.: MA064
  • Model identifier: PowerMac12,1

CPU Upgrades

  • none

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