Flatfoot's Power Mac G5-i7 [DONE]

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May 26, 2010
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Hi everybody,

I know, everybody seems to be modding a PowerMac G5 or Mac Pro these days, but back in the day I had a Power Mac G5 (dual 2.5GHz, liquid cooled, no leaks) and, just before I built my Hack a while ago, I owned a Mac Pro 2.66 Quad, which I upgraded to an 8-core.

Long story short, I just love the looks of that case and thus took the plunge and got myself a PowerMac G5 dual 2.0GHz with a defective PSU off of to put my current Hack into it and upgrade to SandyBridge some time later.

Due to a lack of time (and money) ATM, I have only started taking it apart (no modding or building yet). I'll post again as soon as I've made some progress.

EDIT: OK, now I'm done gutting that thing. Funny how light the case is without all the innards... :)

UPDATE 2011-07-27: So here comes the first bunch of pics...

The G5 in all its glory with my Fractal Design Define R2 standing nearby, all green (well, black) with envy...



The inside, all covered in nicotine dust. The guy I bought it from obviously is a smoker...


My ghetto-style screw-driver put together from all extension parts my cheapo bit set has to offer. Had to secure it with tape since the magnets weren't strong enough to keep it together. It fit the heat sink holes easily but was just barely slim enough to reach the screws, which are pretty close to the heat sinks down there.


The stripped case with the motherboard standoffs removed. Still quite a lot of nicotine smoke residue in there and those two barcode stickers.


Removed the stickers by soaking them in dishwashing liquid and scraping them off a while later with my thumbnail. The sticky remainder that didn't come off that easily had to surrender when I got my isopropyl alcohol I usually use for cleansing CPUs and heat sinks.
I got the smoke/dirt residue off using a micro-fibre cloth and water (and some more alcohol...).


Here's my eSATA case put together from an ATX-case, a modded PSU with a switch in the "short circuit", some eSATA PCI brackets, one port-multiplier, additional fans and, of course, SATA drives.
This bugger is attached to my Hack via a HighPoint RocketRAID 2314 and has been serving me well as a Time Machine backup volume for quite some time now.
Back to the topic: From this case I stripped the front panel harness to solder it to the plug of the original G5 front panel cable.


The front panel harness before the cable mod (2x USB, audio, power switch, reset switch, power LED, HDD activity LED)...


...and afterwards (1x USB, adjusted audio, power switch, power LED). I ran out of heat shrink tubing at some point, which is why the audio cable didn't get any.
The spare HDD activity LED I have left now will be put somewhere behind the front mesh in the vicinity of the power switch/front ports. A reset switch isn't necessary since one can always hold the power switch to perform a forced shutdown and then reboot.

Maybe I'll route a FireWire port to the front from my FireWire PCI card but I don't think I'm ever gonna use the front USB/FireWire/headphones anyway. This was mainly about the power switch and LED...


That's it for now. The gluing, dremelling and hacksawing will have to wait until after this semester's exams.

BTW: Changed the project's name again. Instead of a PowerHack G5-i7 it's a PowerMac G5-i7 now. I mean, with this case it's as close as it gets to a Mac and I think we don't have to discuss the "power" part of the name... ;)

UPDATE 2011-08-01:

Just got a parcel from mikemelbrooks (thanks a ton!):


That's the cage I got today and the one I had from my G5 case.
Now I have the two HDD cages I need, for now... :thumbup:

UPDATE 2011-08-05:

Got some stuff today (see this post for a description):


For now, I only had the time to put the new 92mm fans into the rear fan assembly.
Reusing the original rubber pins wasn't all too easy. Well, I got them out quickly using my Swiss Army knife; I just pushed the spreaders through the holes bit by bit. There was enough room to do that because the original fans have a frame only on one side:


Getting the pins through the holes of the Scythe fans wasn't that easy:


Not a lot of room there, but using tweezers (the ones that are used for plucking eyebrows and other stuff) it went well.

The assembly with the new fans installed...


...and with the cover back on and a PWM Y-cable attached.


BTW: Yesterday I ordered a tube of Loctite 9466 for gluing the mobo standoffs and the extension power cable that connects the PSU to the rear socket to the case.
That stuff has a high shearing resistance, which I think comes in handy since it's going to need it when the screws are put in. I hope it'll be here by Wednesday when I really start working on the case; haven't received a confirmation yet... (just received the shipping confirmation) But I'll also need to get hold of a dead/old ATX board to use in the gluing process until then anyway.

UPDATE 2011-08-06:

Just received the Loctite tube:


And man, that stuff is as poisonous and acidly as it is expensive! Gotta get hold of some acid-resistant gloves...

I still like it better than JB Weld, because you don't have to mix the two fluids by hand; the cap (below the tube in the picture) takes care of that.
Usually you'd also need a special dosing gun to clip the tube into, but I think I'll be able to think of something that lets me push the two sub-tubes simultaneously.

UPDATE 2011-08-11:

Removed the PCI slots frame yesterday (or the day before...?)
Since the weld spots are very small it's quite easy to break them with a small screwdriver and a hammer.


Just the part that's riveted to the back of the case didn't come off until...


...I got my drilling machine from the basement and drilled off the rivets:


Today I merged the two HDD carriers:




This involved drilling and widening screw holes since I didn't want to use glue.
They're not perfectly aligned (~1mm off) and somehow I managed to put the screws in with the points facing up, but still I kinda like it. :headbang:

I also got the hacksaw blades for the top and bottom steel plates and dremel cutting wheels for the back of the case today; by the weekend I should have a dead motherboard to glue the standoffs into the case, too. :thumbup:

UPDATE 2011-08-12:

So... I just did the first two cuts on the back of the case:


"What is he doing there?!" you might think. ;) Well, as stated earlier in this thread I'm going to use the original G5 rear fan assembly, which won't fit in its normal position due to the width of the motherboard rear I/O section.
So I did some measuring and decided to cut out the fan section as indicated by the first two cuts and turn it by 180° so the fans are closer to the other side.
I know this will result in having small gaps where the cuts are now but I'll patch those up from the inside with bits of the part I have to cut out for the upper three PCI slots at the top (or plain aluminium bands [and maybe drill a row of holes in them to let it blend at least a bit better]).
On the other two edges, however, I should manage to get a smooth joint since there will be some excess material I'll have to cut off.

I just made one mistake at the bottom, just above the power socket. There I didn't start cutting in the middle which resulted in the material being too hot and vibrating too much for this narrow section to sustain. Maybe I'll glue it back in later but the fan assembly will be behind the gap anyway.
Hopefully I won't screw up the other two narrow edges...

But in the end the rear is more about functionality than about shiny looks, isn't it? ;)

Ah, and for all of you who are planning to do the cutting in their apartments: Don't. :)
This aluminium dust is really nasty and settles everywhere. Well, you could always ask your spouse to hold a vacuum next to the cutting tool...
I for one will get the rest of the cutting done (as far as I can without knowing exactly at what height I have to mount the Mountain Mods rear I/O shield) in the basement tomorrow.

Another tip regarding rotary blade cutting: You get a nicer (read: thinner) cut by proceeding steadily through the metal at a reasonable pace as opposed to going back and forth between straining and relieving the rotary blade.

UPDATE 2011-08-16:

So, my brother-in-law kindly gave me his old Pentium 4 PC to use for the project; well, I mainly needed the mainboard. Here it is, attached to the Mountain Mods modular I/O panel with an AGP (!) graphics card and a PCI card:


One funny thing about this board: It's a bit narrower (measuring from the I/O shield towards the inside) than a standard size ATX board. This also means that the three mounting holes farthest away from the I/O shield are missing. But that's not a problem; I'll just glue the three remaining standoffs in when I mount my P55 board.

Here's the case with old board in it and some weights to press the standoffs down into the glue. The small weight lying beside the mobo is actually holding (there's a white pin in the corner of the board) it against the rear of the case to compensate for the slightly elastic I/O cover pushing the mobo away from the rear.


Tomorrow the next step will be to rivet the I/O panel to the back since I can't use the pre-made screw holes of the modular I/O panel because they don't line up with the G5's mesh holes.
I'll also dremel away the set-in screw threads of the panel over the PCI slots since they are in the way of the thumbscrews I got for affixing the PCI cards.

One thing about the Loctite glue I used: As far as I can tell by now it does its job very well. There is, however, no way of rinsing the nice mixing syringe that came with it (see above). The syringe has been rendered unusable by the residue that hardened in it.
That means I'll have to mix the glue the old-school way when I use it again. :(

I hope I'll also have the time to refit the fan-holes tomorrow; that's gonna be a bit tricky...

UPDATE 2011-08-17:

Hm, when I just checked the glue I noticed it hasn't hardened completely yet, so I took the G5 from the basement, where it is rather cool, to the flat and installed a professional heating unit to speed up the hardening process. ;)


I also made some HDD slide screws, though differently than originally planned. I used these rubber bands normally used to as gaskets when preserving fruit and vegetables in glasses:


...cut little pieces out of them, punched a hole in the middle of each using a nail and then widened it with a 2.5mm metal drill (by hand).


Two of those pieces put over each screw an then tightening the screws by hand only so far that the rubber pieces make contact with the HDD makes the HDDs sit absolutely securely in the caddies. :thumbup:


UPDATE 2011-08-18:

Received another G5 HDD caddy I bought on Originally it was sold without any screws but after asking the customer support guy dug up 10 G5 HDD slide screws from machines they had lying around for disassembly.
They added them to the purchase – without extra charge. That's really great considering that there are other UK sellers charging ~£10 (incl. shipping to Germany) for a set of four of those screws.

Anyway, now I have extended my drive mounting assembly to fit six 3.5" drives (see above to see how I joined them together):


That should future-proove the case for when I have to add more storage drives.
Let's see what else I can accomplish today...

UPDATE 2011-08-19:

No new pics today since I didn't have my camera with me in the basement yesterday.

I did, however, rivet the Mountain Mods I/O shield to the back of the case. That was fairly easy: I put it in its spot and put in the motherboard and PCI cards like when I glued the standoffs to the case. Then I drilled 2.5mm holes into the I/O shield's frame through a few of the mesh holes. Applying a few 2.4mm rivets was a breeze.

Oh, shearing off the set-in screw threads above the PCI slots (Why? See somewhere above ;)) with the rotary blade went very well, too.

With the rear fan assembly I had to cut off this handle thing at the side. Didn't work with the rotary tool since the plastic just heated up and hardened again (and there were lots of dust!). So I ended up using a handsaw.
I hope the fans have survived the dust (vacuumed them off thoroughly) and vibration... :oops:

Now, however, I'm having a hard time refitting the fan-holes part of the case's back. I'll give it another try tomorrow. Won't be looking good with the holes not lining up properly but it's the back of the case after all and, honestly, I finally want to get this mod over with.
I'm really looking forward to having a silent PSU again and I'm eager to see how the Thermalright Silver Arrow performs compared to the Scythe Mugen 2 Rev. B.

UPDATE 2011-08-20:

Started taking care of the PSU. I'm going to mount it at the bottom of the case, cut a rectangle out of the floor cover and put it back in to hide the excess PSU cables. I figured the easiest way to mount the floor cover properly is to use the PSU housing:


Will have to cut part of that out too, of course.

One great thing about my PSU is that it has a plastic shroud in it that prevents the air pushed in by the fan from just escaping without going through the PSU's innards.


Because of this, although the PSU sticks out of the G5 PSU housing, its exhaust air will go out the back without entering the main compartment of the case.
(The power socket isn't missing. I took it out a few weeks ago when I wasn't planning on using the G5 PSU housing.)

Haven't cut the PSU cover parts yet but the upper divider plate on which the DVD drive is mounted. I don't have a picture of it but it looks just like those of the other people who moved their mobos further to the top.

UPDATE 2011-08-20 #2:

Got most of the plates cut now. I also prepped the extension cable I need to connect the PSU to the rear power plug of the G5 PSU housing. I used an old cable I found in one of my gear boxes.


After soldering I insulated the three solder points separately with electrical tape. Then I wrapped the whole thing up to support the cables.
After each step I made sure all three lines were still OK using a multimeter.

UPDATE 2011-08-26:

I finished my mod over the last few days and here's a writeup of what I did and how it went.

The case itself: Had a few mishaps on my journey, but in the end it worked out quite well.


The PSU housing: I attached the PSU to the floor of the housing using four strong adhesive rubber feet.


...and here it is closed with the cover on it:


Also reattached the clip that holds the plastic door in (I sawed it off the other day).


Turns out, however, that the plastic door won't fit anyway because of the HDD cage that's to be mounted in the front.


Here's the filter-mat, cut to fit. The height was actually perfect, just had to cut off a few centimetres of the side.


Then I had to re-glue a few of the mobo standoffs.


Since the old mobo I used for the first gluing attempt didn't have the left-hand (in the picture) line of screws, I had to glue those in now, using my actual board. Also, because I (or rather the mixing syringe) didn't get the component-mix right back then, three of the feet had fallen off in the meantime.

I had to use weights again since the mobo would lift the standoffs out of the glue otherwise. I was very careful to only put the weights onto plastic parts and the corner screw itself.

And this time I got the mix right. :) Those feet won't come off again.
Here's what I used to apply the glue. (€0.20 syringe from the chemist's)


My front fan assembly: Two Scythe Slip Stream 120mm 1200rpm (original) running at 7V via adaptor; two fan grilles (so the filter mat doesn't touch the blades); three zip-ties; a bit of foam in between the fans.


Then I took out the mobo to exchange the Scythe Mugen for a Thermalright Silver Arrow. There's only a few millimetres between the tips of the heat-pipes and the side door:


Unfortunately, the G5 CPU cover doesn't fit by a few millimetres. It hangs on the tips of the upper-most heat-pipes:


my Airport card – a close fit. ;)


This CPU heat-sink is huge!

Here's a shot of the complete system:


It's a bit crammed but the airflow is OK.
The HDD cage is attached to the floor using double-sided adhesive tape, which works just fine with the weight of the HDDs pressing down.

Now the sad part:
My G5's front panel seems to be dead. :( I even overhauled the cable harness – to no avail.
The thing is I don't have onboard FireWire, so I put the power button ground where there should be FW ground according to the diagram. In the second try, I spliced the USB shield ground to the FW shield ground, so all necessary grounds should be there. Please comment if you have any idea what I might have done wrong.

In between the two tries I ghettoed a short-circuit appliance. :)


When the second try didn't work out either, I soldered a tact switch to the ends of the two cables and put an LED through one of the front grill holes.


A back shot of the hack:


...and the Power Mac G5-i7 in its place beside my desk:



In the end, it's very nice having an Apple case sitting beside my desk again. It's even quieter than my Fractal Design Define R2 was. That's because of the new quieter PSU and the exhaust fans being at the bottom rear instead of the top and the top rear.

On the financial side it was OK, too. I had a hacksaw and borrowed a rotary tool from my parents; just had to buy blades for both of them. My soldering iron was also glad to be used again. :)
Otherwise there were mainly only small parts (except for the new CPU cooler) like two fans for the rear, glue etc.
By selling a few of the G5 parts I already have most of what I paid for the case back in. Selling the Fractal Design Define R2, the XFX PSU, the Scythe Mugen 2 Rev. B and the G5 parts should get me closer to even.

It was frustrating at times – but worth it! :thumbup: :headbang:

UPDATE 2011-08-27:

Notice something?


Riiiight, the front-panel works now! :D

This morning I remembered that yesterday when I had my front-panel cables connected, the hack would always turn on as soon as I connected the mains plug and turn off after a few seconds.
So I figured that there must be a short-circuit of some sort and took out the front-panel PCB to examine it visually and dust it off.

There was nothing to be seen, so just to make sure I did some research on the front-panel wiring diagram.


On the aquamac forum I found the answer: In contrast to the lower three schematics which look at the sockets as they are on motherboards, the G5 front panel connector is shown looking at the plug that connects to the front-panel PCB (looking into the holes of the plug with the wires and the plug at the other end facing away from the beholder).
So in my first and second wiring attempt I just got the wiring laterally inverted. :banghead:

Now I have the power button and LED plus the USB port working. :headbang:
Didn't bother with audio after the first attempt; never gonna use the headphones socket anyway.
Concerning FireWire, my board doesn't have a socket for it.

Now my only remaining concern isn't really to do with the mod itself: Yesterday I noticed that my Geekbench score has dropped from ~10800 in May to ~9800 now at stock 2.93GHz and 1600MHz RAM.
The only hardware change since then has been an SSD replacement (Intel 320 series 80GB for a dead Vertex 2 120GB), which shouldn't affect Geekbench scores.

Feel free to chime in; here's the thread:

UPDATE on the Geekbench problem: Turned out my board was dying. Turbo wasn't working any longer, which caused the decreased Geekbench scores. A few days later, the board failed to boot permanently.

Everything fine again with the new board now. :thumbup:
Last edited:
May 26, 2010
Gigabyte GA-Z170X-UD3
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Re: Flatfoot's PowerHack G5


The case is standing here now completely gutted.

I'm planning to do as little cutting as possible and leave as much of the mesh in the back intact as I can, inserting only the MountainMods I/O panel.

Also, I won't use a motherboard tray but heighten the standoffs a little so that I have as much CPU-heatsing clearance as possible and still have the option to route cables under the mobo.
To accomplish that, I'll use standard ATX standoffs (to be able to use normal screws) but glue some nuts or something similar between them and the back of the case for additional clearance.

The PSU is going to go in the top rear with the fan facing down, which is the most convenient location possible without losing warranty for the PSU like when it is put in the G5's PSU case.
I'll use the original power socket at the bottom, routing a cable down inside.

My only problem ATM is that the double HDD bay that came with my G5 case isn't enough for my current setup, which is why I've already been looking for one or two additional G5 bays for a few days.
Those two to three bays I will hang from the top divider plate (noise-dampened) glued/screwed on top of or beside each other. I'll have to see how this plays together with my plan to keep the air-deflector.

At some later point in time, I'll install a water-cooling setup with a 2x140mm rad (nothing pre-made), which is also to be hung from the top divider plate, but in the front of the case.

I'm really looking forward to getting started on this... :)


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Mar 1, 2011
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Re: Flatfoot's PowerHack G5

If you look at mine, the middle of the thread somewhere pics lol, I used the G5 standoffs and two HDD bays. What I did was glue the two HDD tray together and then match the standoffs to the holes on the rear frames of the HDD trays and JB weld the standoffs.


The standoffs there on the left of the pic by themselves are some I have set up for the HDD trays.
Feb 20, 2011
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Re: Flatfoot's PowerHack G5

HI Where did you get the motherboard tray - it looks perfect for the job.
May 26, 2010
Gigabyte GA-Z170X-UD3
i7-6700K OC @ 4.5GHz
GTX 760
  1. MacBook
Mobile Phone
  1. iOS
Re: Flatfoot's PowerHack G5

eelhead said:
If you look at mine, the middle of the thread somewhere pics lol, I used the G5 standoffs and two HDD bays. What I did was glue the two HDD tray together and then match the standoffs to the holes on the rear frames of the HDD trays and JB weld the standoffs.

The standoffs there on the left of the pic by themselves are some I have set up for the HDD trays.

Hi eelhead,

I've seen your build (and like it). But, as stated above, I'll neither use a motherboard tray, nor the G5 PSU housing. Furthermore, I want to install a 2x140mm rad in the front at some later point in time, so I want to leave room for it there.
From your pic I gather now that I should also take into consideration that I might upgrade my graphics card someday to something longer; so there has to be enough room, too.
Maybe I'll install the two HDD cages (one of which I still have to find) side by side below the top divider.

Yesterday I checked using a PSU I have lying around here and it turned out that even the 24-pin ATX cable fits below the motherboard using only the G5 standoffs, so I might just use those instead of sandwiching something marginally higher.

Anyway, I haven't made up my mind completely and will concentrate on the project in August.
May 26, 2010
Gigabyte GA-Z170X-UD3
i7-6700K OC @ 4.5GHz
GTX 760
  1. MacBook
Mobile Phone
  1. iOS
Re: Flatfoot's PowerHack G5-i7

...hijacking my thread back... ;)

Just came up with a new name for the project (see thread title).

Question to you guys and gals:
I want a PSU that is modular, silent (current XFX PSU is waaaaay too noisy), 80 PLUS certified and powerful enough to provide headroom for a beefier graphics card and water-cooling equipment at some later point in time.
I've narrowed it down to two units now:

Super Flower Crystal Twilight 700W ATX 2.2 (SF700R14HE)


Thermaltake ToughPower XT 775W ATX 2.3 (TPX-775M)

What do you think?
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