GamecubePC

The PC itself consists of an mSTX form-factor motherboard that can support a variety of processors, 260-pin SO-DIMM laptop RAM, and either NVMe or SATA storage depending on the motherboard’s M.2 port specifications. The computer is powered externally through a 19V DC barrel jack power supply. Video output is provided by on-board DisplayPort, HDMI, and VGA ports in the back, and audio input/output can be accessed through the 3.5mm jacks in the front. An optional M.2 WiFi/Bluetooth module can be added with the antennas mounted to a custom rear cover plate that sits above the rear I/O shield.

The 3D printed bottom shell has been designed to both match the footprint of the top shell as well as provide a shelf for the motherboard to rest on. The motherboard is then held in place by the standoffs that adapt the bottom shell to the original top shell. These standoffs also provide mounting points for 50mm intake and exhaust fans through the original top shell’s side vents. The rear standoffs include shelves to mount two custom circuit boards. The intake-side PCB positions the original power switch right below the button in the top shell. The exhaust-side PCB provides a fan hub to distribute the PWM fan signal from the motherboard to the 50mm fans, as well as the CPU fan for motherboards that only have one CPU fan header.

The controller ports are accessible through a Mayflash adapter mounted and wired to the back of the original controller port board. The original memory card slots are now used to access to a 2-port USB hub (based on the FE1.1s USB controller) and a toggle switch to change the Mayflash adapter’s controller mode. The entire front panel assembly only requires one internal USB 2.0 header (2-port) to function.

The power and reset switches are wired to the internal front panel header’s power and reset pins. The underside screws that pass through the motherboard are coupled with rubber bumpers under the bottom shell and allow the unit to be stable on its resting surface.

Project Logs

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Project Update ~ August 2021
RetroModder • 09/24/2021 at 21:04 • 0 comments

I designed a standoff bracket for the Mayflash adapter to fit on top of the original controller port board. It started out as this simple rectangular mount, and then carved it down to a minimal bracket once I had all of the hole locations aligned.

And then I assembled the first unit for testing.

To further improve the design, I added a pair of intake and exhaust fans which required modification to the standoffs. I had a spare ASRock mSTX motherboard so I coupled that with an Intel i5-7600k processor, 8GB of Crucial DDR4-2666, and a 250GB Samsung 860 EVO SSD, and installed it in a platinum shell.

For the exterior 3D printed parts, I found a paint that matched closely to the original Platinum Gamecube color. I then designed a PCB that would act as a Fan Hub for the intake and exhaust fans, and mounts opposite of the Power Switch PCB. Since the ASRock motherboard only has one fan header for the CPU, I had to use that to branch off to the other two fans. The GigaByte motherboard has both a CPU and accessory fan header, so I also designed a PCB for use with that.

This second build will be used primarily as a demonstrator or for prototyping new parts. With the top shell unscrewed from the standoffs, it can easily be taken off or put on in a matter of seconds - the whole assembly goes together very smoothly.
Project Update ~ April 2021
RetroModder • 09/24/2021 at 20:59 • 0 comments

I further improved the MemUSB PCB to include the USB hub on-board, so I do not need to rely on using a tinkerBOY 4-port hub. I also removed two USB ports to add a switch for the Mayflash adapter which allows external toggling between PC mode and Wii-U mode. Then I combined the memory card slot covers and standoffs into one single mount for the board
Project Update ~ March 2021
RetroModder • 09/24/2021 at 20:57 • 0 comments

I've designed a PCB to mount the original Gamecube power switch to, and added a JST header for connecting to the motherboard.
I then worked on integrating the mount for it onto the motherboard standoffs, and figured I'd add an intake fan while I was at it. The fan shown below is a 60mm, but I ended up using a 50mm in the end to save space. The 60mm would interfere with the USB header on the motherboard and make it nearly impossible to plug anything in.

I also made a few modifications to the bottom shell, adding cutouts for the front I/O and a much sturdier slot for the front panel to drop into.
Project Launch ~ November 2020
RetroModder • 09/24/2021 at 20:52 • 0 comments
This project was originally started with the goal of fitting a complete Windows 10 PC inside of a Gamecube case, with the major requirement of running Wii and Gamecube at full FPS and native resolution using Dolphin Emulator. Additional goals were set to retain full functionality of the original buttons, controller ports, cooling system, and more. Based on the specifications of the Mini-STX form factor, I knew one of these motherboards would barely fit inside of a Gamecube shell.

Using a Dremel to hollow out the inside of the bottom shell quickly turned into an ugly JB-welded mess, and there was still no good way to firmly mount the motherboard to it.
So while I thought about the case, I continued to worked on wiring the original front controller ports to a Mayflash Gamecube-to-USB adapter. I found a connector with the proper pitch that allowed me to interface with the original controller port board

I was able to get it to function in both PC (D-Input) and Wii-U mode in Dolphin. With a lack of USB ports on the motherboard, I thought it would be a good idea to install some additional USB ports in the memory card slots, so I designed a custom PCB to handle that using the very low-profile tinkerBOY 4-Port USB Hub. There is only one internal USB 2.0 header on the motherboard, so the Mayflash uses one port and the 4-port USB hub uses the other.

I realized I was going to need a 3D printer to make this build clean, so I picked up an Ender 3 v2. After many tweaks to match the curvature of both the inside and outside of the front panel, I was able to print some standoffs and USB port covers.
I also now had a solution for the bottom shell. Only a few prints were required to get the base very close to the original shape. I then worked on adding access to the motherboard I/O and a slot for the front controller port panel to rest in.

I then had to design some standoffs to go from the original Gamecube screw posts in the top half of the case to the PC motherboard's mounting pattern. A cover was also printed that goes above the motherboard rear I/O shield, and has mounting holes for the WiFi and Bluetooth antennas.
Features
- Functional controller ports using Mayflash USB adapter
- Added 4 USB ports to front panel
- Accessible front motherboard I/O from outside of case
- WiFi/Bluetooth antennas connected to internal dual wireless card
- Large M.2 heat sink (drive gets quite hot)
- Sturdy structure and assembly
Future fixes
- Top shell LED only comes on when the Mayflash adapter is in a certain mode. As soon as I toggle the switch, it turns off power to that LED, so I need to source power from somewhere else
- Perhaps part of the same problem above, the reset switch actually has power going to it in a certain mode of the Mayflash adapter, which holds the reset pin on the motherboard high and causes the computer to continuously power cycle until I switch modes
- May be more convenient to relocate the switch on the Mayflash adapter to the front panel
- No issues with cooling the CPU yet but may install some small fans using the original intake and exhaust vents
- Design a PCB to mount the original power switch to, and then 3D print a mount for it