Introduction

The Power Mac G4 MDD Uses two system fans, an optical fan (for the optical drives), and a main system fan (cools the CPU, the hard drives, and the graphics card).

Parts

No parts required.

The Power Mac G4 MDD: the last, and the fastest G4-based Mac.  This computer boasted up to a Dual 1.42GHz PowerPC G4 CPU (though I have a single 1.25GHz). Six USB ports.
  • The Power Mac G4 MDD: the last, and the fastest G4-based Mac. This computer boasted up to a Dual 1.42GHz PowerPC G4 CPU (though I have a single 1.25GHz).

  • Six USB ports.

  • Four FireWire ports.

  • Assorted SCSI (SCSI50/SCSI68)

  • Assorted Audio

  • Video (ADC & DVI)

  • Networking (RJ-45 Ethernet/56k Modem)

  • Some later model MDD's (such as the dual 1.42GHz) Have a FireWire 800 Port Here:

Pull on the side lever and lower the side of the case. Pull on the side lever and lower the side of the case. Pull on the side lever and lower the side of the case.
  • Pull on the side lever and lower the side of the case.

The hard drive cages are located here.
  • The hard drive cages are located here.

Cage 1 Start by removing this screw. Remove the IDE ribbon cable from the motherboard.
  • Cage 1

  • Start by removing this screw.

  • Remove the IDE ribbon cable from the motherboard.

Now, remove the power connecton from the drives. Now, remove the power connecton from the drives.
  • Now, remove the power connecton from the drives.

Now, push this tab down, and pull the cage towared you. Now, you can set cage 1 aside. Now, you can set cage 1 aside.
  • Now, push this tab down, and pull the cage towared you.

  • Now, you can set cage 1 aside.

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Cage 2: Remove this Phillips screw:
  • Cage 2:

  • Remove this Phillips screw:

  • Disconnect this IDE ribbon cable from the logic board.

It's likely that there is a cable clip holding the ribbon cable to the case. To remove it, push the end, and it should pop up.
  • It's likely that there is a cable clip holding the ribbon cable to the case.

  • To remove it, push the end, and it should pop up.

With the clip free, pull on this tab, lift the cage up, until it clicks, and pull it away. Now, set the cage on top of the CPU, and remove the power connectors. Now, set the cage on top of the CPU, and remove the power connectors.
  • With the clip free, pull on this tab, lift the cage up, until it clicks, and pull it away.

  • Now, set the cage on top of the CPU, and remove the power connectors.

Once the cables are free, set the drive cage aside. To remove the hard drives from the cages, remove the four screws on the sides of the cage that are connected to the drives, than slide the drives out.
  • Once the cables are free, set the drive cage aside.

  • To remove the hard drives from the cages, remove the four screws on the sides of the cage that are connected to the drives, than slide the drives out.

  • The two cages are cross compatible and can be put in either rack.

  • The MDD does not have a 128GB drive limit like older macs, My MDD has 3 Drives (A 400GB Hitatchi Deskstar, 40GB Seagate Baracuda 7200.7, and a 30GB Quantum Fireball LCT).

  • Note the ID jumpers on the two drive set. One is set to Master, the other to slave. A single drive can be set to Cable Select.

Start removing the optical drive cage by removing the back cover. Start removing the optical drive cage by removing the back cover.
  • Start removing the optical drive cage by removing the back cover.

Now, remove the IDE and power cables. Now, remove the IDE and power cables. Now, remove the IDE and power cables.
  • Now, remove the IDE and power cables.

Remove these two Phillips screws: Now, pull the cage away from the front until it is free. Now, lift the cage out.
  • Remove these two Phillips screws:

  • Now, pull the cage away from the front until it is free.

  • Now, lift the cage out.

To remove the drive from the cage, remove the four screws on the side of the drive, and pull the drive out of the cage. My MDD has a 3rd Party 22X SuperDrive, for burning DVD's in Leopard (Thank You Generic Drive Support!)
  • To remove the drive from the cage, remove the four screws on the side of the drive, and pull the drive out of the cage.

  • My MDD has a 3rd Party 22X SuperDrive, for burning DVD's in Leopard (Thank You Generic Drive Support!)

Optical Fan: Remove these two Phillips screws: Now, slide the plate towards the case, and lift it up, and off.
  • Optical Fan:

  • Remove these two Phillips screws:

  • Now, slide the plate towards the case, and lift it up, and off.

Once the cover is removed, disconnect the power cable and thread it under the dust shield. Now, lift the fan straight up and out.
  • Once the cover is removed, disconnect the power cable and thread it under the dust shield.

  • Now, lift the fan straight up and out.

System Fan: Disconnect the optical drive IDE cable from the logic board.
  • System Fan:

  • Disconnect the optical drive IDE cable from the logic board.

  • Now, remove the system fan cable.

Now, grab the system fan by the sides and pull it up, it should come free, the system fan is very large and loud, compared to standard sized fans. Now, grab the system fan by the sides and pull it up, it should come free, the system fan is very large and loud, compared to standard sized fans. Now, grab the system fan by the sides and pull it up, it should come free, the system fan is very large and loud, compared to standard sized fans.
  • Now, grab the system fan by the sides and pull it up, it should come free, the system fan is very large and loud, compared to standard sized fans.

Conclusion

To reassemble your device, follow these instructions in reverse order.

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Chris Green

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Das waren halt noch service- und support-freundliche Macs …

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