Retro Power Mac G5 Hackintosh
A few weeks ago our landlord was spring cleaning, and a pile of old computer parts was marked for disposal. Among a dusty pile of floppy disks and old Compaqs, something shiny caught my eye: a Power Mac G5.
For those that never had the opportunity to use the Power Mac G5, it was Apple’s top-of-the-line system from 2003 to 2006, and probably the thing I coveted most in high school.
The G5 was a 39.2 lbs beast in a gorgeous, machined and anodized aluminum chassis — it was a monument to Steve Jobs’ attention to detail, and the beginning of Apple’s obsession with aluminum that continues to this day. The G5 is unusably slow by today’s standards, but in 2003 Virginia Tech’s System X supercluster built with G5s was the 3rd fastest super computer in the world (there’s some awesome computer history in this old System X promo).
Coincidentally, Avidan and I needed an office computer to run software that was too slow on our laptops (Eagle, CAD, Adobe Creative Suite, Microsoft effing Excel, etc). This was the perfect opportunity to fulfill my dream of owning a G5 and build an office workstation: we decided to retrofit a modern workstation into the G5 chassis.
It was clear from the moment I opened the case that this project would not be as easy as I initially thought: every part of the G5, starting with the latch that opens the case, was obsessively designed and over-engineered.
The first thing you notice when you open the G5 is the massive heatsink for the CPU. While big heatsinks are not unusual in workstations, the G5 heatsink cover is anodized the match the case, and has “G5” added to the surface in aluminum and polished.
Upon further inspection, the heatsink and attendant CPU are actually fixed to a custom carrier board, so CPUs and heatsinks could be easily added or upgraded as a single unit. The heatsink is not visible at all during normal operation, and the carrier board saves only a few steps compared to a traditional CPU swap. Clearly little expense was spared in designing every part of this computer.
Continuing the disassembly, I removed an anodized aluminum plate at the bottom of the G5. I assumed this was an enclosure or shield for the power supply, but removing the plate revealed… a fully enclosed power supply. It turns out this plate is purely cosmetic. The power supply (light blue, visible at bottom of picture) came from a supplier in a powder-coated steel enclosure; my guess is that whoever designed the interior of the G5 could not stand the powder-coated steel clashing with the aluminum enclosure, so they added an aluminum plate on top of the power supply. Again, none of this is visible during normal use.
The next step was removing the fans — all 6 of them (not counting two in the power supply, hidden under the plate). The intricate mechanical design of the G5 is apparent here as well. All of the fans were a (custom) light grey injection molded plastic, attached to a light grey plastic (also custom) racking system with silicon screws instead of metal screws. Silicon screws improve vibration dampening thus reducing fan noise, but are tricky to install.
For those of you that have worked with plastics, you know that cleanly injection molding light colors is a pain in the ass. Apparently in this case it was worth it so the fans could match the aluminum chassis.
After the fans, I removed the power supply. As you can probably guess by now, the power supply has an unconventional form factor that lays flat across the floor of the chassis — presumably so that the beautiful chassis, fans, heatsinks, and motherboard wouldn’t have to associate with something as mundane as a power supply.
The power supply is attached by screws that come through the bottom of the chassis. Upon closer inspection, these screws have a thoughtful surface finishing that is not present on any other screws in the G5. To be clear, these are screws underneath the computer that are not visible unless you flip the entire computer upside down — but because they are technically visible from the exterior, Apple opted to give them a bit of extra finishing.
As previously mentioned, the power supply is hidden under an anodized aluminum plate, except for one unavoidable part: the IEC C14 power plug in the rear. Unsurprisingly, the G5’s IEC C14 plug is the same light grey plastic as the fans, and the supplied power cable is white. No detail left behind.
At this stage, the only parts left in the chassis were the motherboard and the drive brackets. While these components were also custom, they could at least be removed with a regular screwdriver (and the occasional torx driver, but who’s counting), leaving the fully stripped aluminum chassis. To this day this chassis remains one of the nicest desktop cases ever built:
The entire time I was dissembling the G5, I kept wondering what poor contract manufacturer had to deal with all this unconventional custom work. A plaque on the chassis reveals how Apple did it: Assembled in USA. 💸💸💸
With the G5 disassembled, it was time for the hard part of the project: modifying the chassis to accept modern computer parts. We chose parts that would give us significant computing and graphical horsepower while fitting in the G5 chassis with minimum destructive modification (the actual part list I used is here).
Luckily, I found The Laser Hive, a British company that provides plans for aluminum G5 adapters for modern computer parts free of charge. For those without access to a water jet or strong laser they also sell complete adapters.
The first custom part we had to make was a bracket for 120mm cooling intake fans. We chose 120mm fans because they pretty efficient and quiet. Taking a note from the original G5 design, we used silicon screws to hold the fans to the intake bracket.
The next custom part we had to make was a rear adapter plate that would allow us to install a 120mm exhaust fan, and expose the ports on the new motherboard. The new motherboard would be held in place by a laser cut transparent acrylic tray. This was the most destructive part of the retrofit: we had to cut part of the chassis’ rear mesh panel with a rotary cutter to accommodate the new adapter.
We also discovered that — surprise — the front panel (including the power button) on the G5 is proprietary and matched to the original non-standard motherboard. In order to use the panel to control the new motherboard, we had to wire a custom cable harness. A big thanks to the hackers at InsanelyMac who provided wiring diagrams.
With all the custom adapters installed, we could finally begin assembling the new computer inside the G5. This was the easiest part of the entire project.
With the components assembled in the chassis, we had to make one last custom part: the power supply. The new components required a modern power supply, but we wanted to keep the light grey power plug from the original power supply.
This was accomplished by splicing the power and ground wires in the bottom half of the original power supply enclosure to a power cable leading to the new power supply. This also allowed us to install the power supply in using the nicely finished screws discovered during disassembly.
With the power supply installed, the hardware portion of the retrofit was complete! We used as much of the original chassis as possible, leaving only the optical drive bay unused. I’m considering adding a few terabytes of disk storage in its place, or possibly a second GPU.
After so much work to preserve the glory of the G5 chassis, it felt wrong to install Windows or Linux. This led us to the next phase of the project: making a hackintosh.
Hackintosh is a type of computer in which a non-Macintosh or unsupported computer is converted to run a Mac OS… The Hackintosh technique was initiated when hackers amended pre-released Mac OS X versions by avoiding Apple’s Trusted Platform Module (TPM), which uses cryptography to secure sensitive information. — Technopedia
I made my first Hackintosh in 2011, when I hacked an install of Mac OS X Snow Leopard on a Dell Inspirion Mini (lol netbooks) instead of studying for finals. It was a cool proof of concept, but the sound didn’t work and the processor ran at an unbearable 170+ degrees Fahrenheit.
Since then, the community and support around Hackintosh has gotten significantly better. If you want to build a Hackintosh, Tonymacx86 is a one-stop shop for parts lists, software tools, patches, and guides.
Every Hackintosh has its share of quirks, bugs, and baffling behaviors that need to be stamped out — ours was no exception. For the sake of brevity I’ll spare the details, but I ran the G5 partially disassembled for a week until I got macOS stabilized.
Ultimately, the process was longer and harder than I had anticipated, mostly due to Apple’s absurdly custom hardware design — but now I have the G5 I’ve always wanted running at Mac Pro speeds for less than the cost of a MacBook Pro.
There were a few resources without which I would have struggled a lot more. They are sporadically mentioned throughout the post, but worth mentioning again:
- Tonymacx86: everything you need to build a Hackintosh, and an active forum that has covered just about every arcane bug in the process.
- The Laser Hive: plans and parts made for adapting G5 hardware.
- G5 ATX Cable: if you retrofit a G5, these premade cable harnesses will save you a LOT of time.
- Dremel: the handheld rotary tool I used for to cut the aluminum chassis when needed. Even if you aren’t modding a case, you should own a Dremel for its sheer versatility. A real pillar of DIY culture.
- TechShop: want to fabricate your own parts, for a Hackintosh or anything else? TechShop is one of the best community maker spaces!
- PC Part Picker: the best project management tool for any sort of computer build.
- Bolt.io: another hardware VC with a great blog of tear downs. Don’t miss their excellent analysis of Juicero, another over-engineered piece of hardware.
- iFixit: free repair manuals and tear downs of hundreds of products with high resolution photography. If you want more info about the G5 process, check out their super detailed guide. Also a great source for specific tools needed for disassembly.
If you have built or plan on building your own Hackintosh, let me know! firstname.lastname@example.org