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I've been using this modded case since 2005.  A couple of months ago, I decided to upgrade the major components (motherboard, CPU, RAM, video, and PSU).  Everything was designed to be fully plug-and-play from the get-go, but I was still pretty amazed at how easy it was to replace every major component without further modification.  So, I decided to make a post about it.

To begin, this isn't your grandmother's G5 mod!!  Unlike other G5 mods, I had two strict requirements:
(1) The case needs to look completely stock from the outside, and it needs to be fully functional.
(2) Swapping major components (motherboard, PSU, etc) needs to be completely plug-and-play.

I apologize for the crudity of the images.  I had to boost the exposure time to get them to come out at all.  When you boost the exposure time a lot, and you don't use a tripod, you get a blurry mess (unless you have exceptionally steady hands).  I'll be sure to retake them, but for the time being, here they are:





So again, my two requirements are:
(1) The case must be fully functional, and look fully stock from the outside, including S/PDIF input and output!!
(2) Replacing the motherboard and power supply needs to be 100% plug-and-play.

It took a considerable amount of engineering to meet these requirements, but we can break it down into four basic categories:

Front panel I/O ports
I hacked apart a SilverStone FP32 to get my front panel USB, FireWire, and headphone ports.  Each of these ports had a tapered tip, which I cut off for a better fit.  I chose the FP32 because it supports Intel High Definition Audio (HDA, or Azallia).  HDA ports can automatically mute the speaker audio when head phones are plugged in.

Rear panel I/O ports
This was the hardest part of the project, and the part where most people resort to cutting a hole in the back of the case.  But there's a better way!!!  The rear panel ports in the standard ATX design are recessed about a half an inch, but the ports on the G5 case are flush.  This gives us a half-inch to play around with.

My solution was to make a port adapter.  One side of the adapter contains all of the G5's female ports.  Each port has short leads to its corresponding male plug.  The adapter itself is affixed to the inside of the case.  So, the idea is, when you want to install a new motherboard, you simply attach the leads from the port adapter to the new motherboard.  The plugs need to be shaved down, so that they're flush with the motherboard ports when plugged in.  This is important.

In my particular case, I actually etched a simple circuit board, just to make things neater.  I scavanged each of the G5's ports from a broken G5 motherboard, and mounted them to my circuit board.  The board traces simply relocate each port's pins to a cluster of PATA pins (which I scavanged elsewhere) on the board.  I attached my leads to these pins by cutting apart standard ATA cables.

The S/PDIF ports required some extra effort.  The S/PDIF input port was scavanged from GigaByte's S/PDIF-in bracket, and plugged into the S/PDIF-in header of the motherboard.  The output port was the original one taken from the G5 motherboard.  Unfortunately, the GigaByte board didn't have a S/PDIF-out header, but it did have a digital output header, intended for use with an HDMI graphics card.  Luckily, it turns out that HDMI Audio IS S/PDIF, but the digital output header wasn't powered.  So, I drew the power from the input port, and presto!  I now have fully working S/PDIF Input and Output!!!!

Motherboard mounting
To mount the motherboard, I basically pulled out each of the G5's original standoffs (you can pull them off with pliers and a slight rocking action).  Each standoff has a base and shaft.  The base was originally recessed into the wall of the case.  If we use these in different locations, they'll be "on top" of the wall, instead of recessed.  So, in order to re-use these standoffs in the ATX locations, I had to grind them down a little bit, first.

Next, I cut out a bunch of lexan squares.  Half of the squares have a large diameter hole that fits around the base of the standoff.  The other half have smaller holes that fit around the shaft, but not the base.  When these two layers of lexan are glued together with epoxy, we end up creating a standoff with a very large base.

I screwed each of my modified standoffs into the proper locations on my ATX motherboard, applied epoxy to each base, and stuck the whole motherboard to its correct position within the case.  To align the motherboard, I used a graphics card and a PCI card to make sure that the cards fit properly into the motherboard slots.

Power Supply mounting
The power supply is just your standard ATX PSU --Well, maybe not exactly (see specs).  I gutted the original G5 PSU (also broken), removed the cover, and fabricated a new cover to hold an ATX power supply.  To power the unit, I cut off a three inch section of power cable, and soldered one end to the original G5 power connector.  The other end simply plugs into the PSU.

Other considerations
As you might be able to make out from the pics, I've also fabricated a basic drive cage.  I intend to buy a hot-swappable ATA enclosure to replace this; I just haven't gotten around to it yet.  I'm also going to mount the optical drive differently.  But for now, it works.

Specs
GigaByte GA-EX58-UD5 Socket 1366 motherboard
Intel Core i7 920 @ 4.0GHz
6GB OCZ DDR3-1600 RAM
NVIDIA 8800GT SLI
Tuniq Ripper 1000W power supply
Snow Leopard (Store bought, but I won't get into that)
Vista x64 (MSDN license)

Last edited by Mr. T (2009-09-26 7:56 pm)