Power Mac G4 (Mid 2003)

Leave it to Apple to completely confuse the market by releasing a “brand new” 1.25 GHz  Power Mac G4 model at the same time it announced the first Power Mac G5s. Like the 2002 Mirrored Drive Doors Power Mac G4, this model can boot into OS 9 as well as OS X. It must be time for Apple to unload the last of the old hardware.

Mirror Drive Door Power Mac G4The June 2003 model is essentially the same as the 2002 1.25 GHz dual processor model, except that it is also available with a single CPU. Unlike the Early 2003 FireWire 800 Power Macs, it has the ability to boot into OS 9, uses plain old 802.11b AirPort cards instead of the newer, faster 802.11g AirPort Extreme, and doesn’t include FireWire 800.

This model has a 167 MHz system bus, two media drives bays (so you can have a SuperDrive and a fast CD burner), four RAM sockets, and three independent drive buses that each support two devices. An Ultra ATA/33 (ATA-4) bus is used for the optical drive(s), Ultra ATA/100 (ATA-6) connects to the stock hard drive, and there’s also an unused Ultra ATA/66 (ATA-5) bus. Only the ATA/100 connector supports drives over 128 GB capacity. There are four 3.5″ hard drive bays inside the G4.

Although the MDD Power Macs support up to 2 GB of RAM, Mac OS 9 is only able to access up to 1.5 GB.

Watch out for Apple’s claim of “four USB ports” – there are two on the computer and two on the keyboard, just like the old G4s. Plug in the keyboard, and you have three available. Plug in a USB mouse, and that drops to two.

You should have the most recent firmware installed in your Power Mac G4. The newest version for Mirrored Drive Doors models is Power Mac G4 Firmware Update 4.4.8, which is only for Mirrored Drive Doors Power Mac. To install this firmware update, you must boot into Mac OS 9.2.2 from a writable partition (not a CD).

  • Got a G3, G4, or G5 Power Mac? Join our G-List Group.
  • Got a G4 or want to know more? Join our G4 Group.
  • Our Mac OS 9 Group is for those using Mac OS 9, either natively or in Classic Mode.
  • Our Jaguar Group is for those using Mac OS X 10.2.
  • Our Panther Group is for those using Mac OS X 10.3.
  • Our Tiger Group is for those using Mac OS X 10.4.
  • Our Leopard Group is for those using Mac OS X 10.5 and 10.6.


  • introduced 2003.06.23 with 1.25 GHz single, 256 MB, 80 GB, Combo at $1,299, 1.25 GHz dual identically configured at $1,599; discontinued
  • Compatible Mac OS Versions
  • CPU: 1.25 GHz PowerPC 7455
  • Bus: 167 MHz
  • Performance:
    • Geekbench 2 (Leopard): 1047 (dual), 703 (single)
    • Geekbench 2 (Tiger): 1048 (dual), 702 (single)
  • RAM: 256 MB standard, expandable to 2 GB (although Mac OS 9 will only recognize 1.5 GB) using PC2700 memory in 4 DIMM slots
  • Video: ATI Radeon 9000 Pro (Nvidia GeForce 4 an option); DVI and AGP ports, includes DVI-to-VGA adapter
  • VRAM: 64 MB
  • L2 cache: 256 KB on-chip L2 cache
  • L3 cache: 1 MB on single, 2 MB per CPU on dual
  • Hard drive: 80 GB 7200 rpm ATA/100
  • Combo (CD-RW/DVD) drive standard; SuperDrive available
  • internal Zip 250 drive (optional)
  • 4 64-bit PCI slots
  • Modem: internal 56k v.92
  • Microphone: standard 3.5mm minijack, compatible with line-level input, not compatible with Apple’s PlainTalk microphone
  • FireWire 400: 2 ports
  • USB: 2 USB 1.1 ports
  • Ethernet: 10/100/gigabit
  • antenna and connector for AirPort card
  • size (HxWxD): 17.0″ x 8.9″ x 18.4″
  • Weight: 42.0 lb.
  • Gestalt ID: n/a
  • PRAM battery: 3.6V half-AA
  • upgrade path: none yet, although CPU upgrades are likely
  • Order no.: M9145

Accelerators & Upgrades

Online Resources


  • Mac OS X 10.5 Leopard boot times for Power Mac with the GeForce 6200 fall into the 4-5 minute range, and was initially suggested that you install Leopard with the Mac’s original video card to avoid slowing down the process. “gotoh” has posted the fix in The Mac Elite Forum. The delay is due to Leopard not supporting temperature sensors in G4 Macs. Simply remove AppleHWSensor.kext from /System/Library/Extensions, and the delay goes away.

Short link: http://goo.gl/tUhPYd

searchword: mdd2003