My MDD died a horrible death. One morning I went to boot up and got a black screen and no curser of any type. 28 seconds later, the main 120mm fan came on at a level I had never heard before, like a jet engine. The Gurus gave me a slew of tips. Tried them all with the same result. Jason at Giga offered to test my CPUs board. Rick and Jason collaborated to send me the Giga MDD upgrade. Still no go. Took the MDD to the local Apple Store Genius Bar, armed with my 3 year AppleCare, and the Genius Level 1 guy ran thru a whole series of tests while I watched. He concluded it was the logic board. Less than 24 hours later I received a call that the MDD was ready for pickup. Bill was just under $500, new version 3 mobo, my cost ZERO. AppleCare at $249 paid off very well. Both Rick and Jason were very kind and I bought the GigaBump.

What I had: MDD G4-1.25GHz DP dual boot, FW400, 167MHz bus shipped 09/25/2002.
Now: GigaBump MDD G4-1.42GHz DP

Some pics of the GigaBump MDD upgrade installation. I dumbed down the size and resolution of the pics to keep them small. Anyway...

Pic below shows what is inside the box. The foam packing inside is industrial strength. The CD is Drive 10 and has a serial number on the back side of the envelope. The power connectors can be used to connect the 120mm fan to the Giga board to allow the Giga to control and slow down the fan considerably. Instructions say that you do not have to do this, that you can leave the 120mm fan as OEM connected and I left it that way. Note also the two spacers in the plastic bag. They will be used later. The instructions are in color and on both sides of a heavy sheet.

Pic below is of the OEM heatsink. Note how tall it is. 2 of the 4 Phillips screws for removing it are at the bottom, the upper two are obsured by the fins. On the lower right, just that one screw, don't mess with any other screws on that assembly. Save the screws for later.

Pic below is the OEM CPU board. Between the two holes on the right you can see where the board connects to the mobo. Note the three silver spacers on the lower and upper left and the upper right. Those are where you unscrewed 3 of the 4 Phillips screws to remove the OEM heatsink. On the right, the entire assembly is still there. All that was removed was that 1 screw.

This pic below is the real key to the operation of removing the OEM CPU board and installing the GigaBump. Don't mess with the black rail on the left. It is a frame that either CPU board slides into and out of. Raise the opposite end of the board, the right side, to disconnect the board from the mobo. Then continue to raise the board while pulling toward the right. Note that I have already partially raised the board and disconnected it from the mobo and the board has already partially slid out of the black rail.

What could be easier. Following the instructions for the GigaBump, turn it over and remove the protective cap from the connector, then turn it right side up and spread apart those bracket fingers on the upper and lower right, angle the GigaBump right side up, slide it part way into the black rail and lower the GigaBump while continuing to slide left until the board contacts the mobo connector. Then once lowered and in the black rail all the way, push down on the right side of the assembly to mate the board with the mobo. You will hear and feel the the connection to the mobo is made. Those two spacers in the plastic bag slide over the OEM spacers on the left side. Screw the GigaBump down with the 4 screws you saved.

Just another view of the GigaBump. Note its much lower profile.

All of this is in the instructions. I did amplify somewhat on the CPU board removal and GigaBump installation. Big temptation to mess with the black rail or the other screws on the right side assembly.

The much lower profile of the upgrade allows much more air to pass from the 120mm fan, between the upgrade and the vertical double drive bay, and out the back. I also cannot hear the Giga fan. The entire inside, the PCI slot area, the CPU area, and the vertical and horizontal drive bays are all much cooler. What could be finer, a well engineered upgrade. k