Hi everyone, I'm a long time lurker of the forums and thought I would share my latest project.

I have had an old "Sawtooth" PowerMac G4 lying around my office/man-cave for a couple of years just being used for website and Flash testing. It is now ten years old as of January and it’s about time to retire it forever as the ancient and completely obsolete guts it has now make it next to useless when compared to the quad core Hackintosh tower that replaced it. I do like this case as it's a classic but its time as a PowerPC based Mac is over. And I am sure that there are a lot of people here who would love to see a way to fit a full sized tower cooler into a G4 case, consider this guide a way to do it. Looking in my parts bin I found more than enough (somewhat) modern components to put this thing together. Please note that this is my first mod, all input is welcomed.

Motherboard & CPU: Asus P5QL-EM and an Intel Pentium Dual Core E6300.



Video Card: BFG GeForce 9800GT 512Mb with AC Accelero 1 Rad.


Memory: 4Gb of OCZ DDR2-1066.


CPU Cooler: OCZ Vendetta 2 that I grabbed for $12


HD: A WD 320Gb SATA with a stock Intel heatsink thermally glued to it (it was part of my old folding box).


PSU: An OCZ 400W "Fatality" that I picked up for about $25 last summer.


And finally, a wireless card with a pretty good antenna as this machine will be used all over the place.



Here's what I am starting with:

The Victim


Arrrgh ancient PowerPC, AGP and IDE!


Specs


Rear end


Not a lot of connectivity here



The G4’s old motherboard is approximately the same size a Mini-ATX board with four standard spaced expansion slots, the motherboard posts do not line up with ATX standards so they will have to be removed and replaced. The rear panel will have to be altered to accommodate an ATX IO plate, and the optical drive bay will have to go as in its current location will hit the RAM and likely the tower style CPU cooler too when the side of the case is closed using its new M-ATX internals.

So let’s tear this thing apart.



All of the plastic panels covering the steel interior are secured by the acrylic handles and feet using flat hex head socket caps, the whole thing came apart fairly easily and I was surprised by a few things I found. Considering that this thing is a decade old it was interesting to find a wireless antenna running from the motherboard section to both sides of the case, I’ll keep this to see if it can be put to use later in the project.

Apple hid a bunch of the system controller chips under the motherboard including a made in Canada system controller using the case itself as a heatsink, and an Intel AGP controller. Though kind of nostalgic all of this old junk has to go.




So with the machine stripped of its plastic shell and old PowerPC and IDE components I am left with this:







Here's where the big differences between my project and all of the other G3/G4 case mods start.

Now I have seen many examples of this type of project before, but to be blunt most G4 case to ATX conversions look like real hack jobs. One of the sources of problems with retrofitting this case for modern ATX components is that every single mod I have come across uses the old PSU mounting bracket that runs the whole length of the case, this greatly restricts the height of the CPU cooler (as seen in the image here from someone else's project) and provides a potential cable routing nightmare as ATX power supplies are not made for this type of case layout as the distance between the PSU and the MB changes between the open and closed positions of the case.

So I started with a seemingly easy solution; remove the old optical drive/PSU bracket and relocate the PSU.

The most logical position considering what else has to fit in there is to put it somewhere in front of the case and having it exhaust out of the bottom as the old PSU exhaust location will be fully occupied by the CPU tower cooler.

Another difference between MacBane and other G4 mods is where the hard drives are located, Apple originally left room for drives to be mounted onto the bottom of the case using some steel plates. I will use a custom aluminum bracket that will hold both the hard drives and the PSU to be located in the front of the case.

Now all I have to worry about is clearance for the video card when the case PSU/HD bracket is mounted as the 9800GT with the Accelero S1 cooler needs about 10" to fit from the expansion card slot opening.

My next step is to remove the old PSU/Optical drive bracket seen running along the middle of the case. I have a USB DVD-R if I ever need to used optical media down the road:



All that is required to remove it is to drill out a few rivets, super easy:


Looking better already:


Now to size up a M-ATX board using a junk board filled with PCI Cards for alignment to get an idea of how much of the back plate has to be edited.




So after a little measuring it looks like the easiest solution is to remove the entire backplate from the red line (drawn in the picture below) over to the right. Of course all of the expansion slots use the same piece of metal as the backplate and had to have a new rivet added to prevent any warping or wandering that might cause the motherboard to be mounted incorrectly later on in the project.


This tab has to go too if I want to use my audio jacks:


Rivet location:




Now for some sparks:




And the end result of two cuts and a few rivets being drilled out; a nice open IO location ready for a new MB.


The standard ATX IO plate won't be used, instead I plan to build a custom one out of either Acrylic of Aluminum sometime soon.

Next up it's time to figure out where the new motherboard standoffs are going:


Used a Popsicle stick with a dab of paint to mark the holes.


Nice and easy to see where to drill now.


I also figured out where I will be making a few edits to door latch mechanism that fits under the motherboard as I have new standoff locations to contend with.


Planning out the bracket dimensions using a POS power supply (the magic smoke left it long ago).


Time to give this case some real ventilation by ditching the grill on the side 120mm fan and adding another 120 to the bottom of the case.


The old PSU location is getting a face lift too as it will now be home to twin 80mm exhaust fans that will help keep this machine nice and frosty by comparison to the toaster oven it used to be.


After a marathon cutting session this thing is ready to breathe easy.


Time to tap the motherboard standoff holes.


And finally the construction of the HD-PSU bracket starts:






I test fitted it with the dead PSU and I am happy to report it fits perfectly, if it didn't I would be seriously ticked off.


Rails for two hard drives added


I used a pair of ancient 1 and 2Gb drives from the 90's for test fitting, so far looking good and there won't be many cables visible when I am done...awesome


Next components:

Cheap but decent Acrylic Panels:



Clear Polycarbonate 6mm thick and bullet resistant



Time to put this stuff to work.

As for other plastic components of the case (referring to the outer shell of the machine) I picked up some Krylon Fusion in Gloss Black, Flat Black and Flat White. And for the metal parts some good old Tremclad and some translucent red.



As for the case progress I removed the last section of the old IO panel as it will make adding a custom one much easier later in the project.



I will be building the motherboard standoffs and modding the latch panel next.

Time to get the motherboard standoffs installed, I am using some 6-32 x 3/4 machine screws inserted from the backside of the case into the holes I tapped several steps ago.



I am keeping this as simple as possible and used some PVC tubing to make some 8mm non-conductive spacers to keep the motherboard suspended above the door latch.



Nice and easy.



Next up was to mod the sliding door latch that goues under the motherboard using a 3 amp rotary cutter.



Two minutes of work later the latch pane now fits with the new motherboard standoffs.



I then started to fit the test motherboard onto the new standoffs to make sure everything was aligned properly.





Looks secure to me.



Now its time to attach the HD-PSU rack to the case, you probably get a pretty good sense of where all of the cables will be going from the shot below.



Now comes the fun part to see if I measured everything correctly, the rack is designed to be mounted 25mm above the base of the door, you can see the riser supports below.



One tool I think will be very handy is my laser level, by lining it up with the HD-PSU brackets outermost edge I see that I have a few millimeters of material to remove from the door catches on the front of the case.



More to follow shortly

Any comments or input is welcomed.