Recently I’ve started dabbling in the fine art of console modification, and I saw this post – it inspired me to create my own copy of Pokemon Yellow in SNES format! I had a really grubby Super Game Boy cartridge lying around that wasn’t being used, so quickly ordered a copy of Pokemon Yellow from eBay and got to work. I followed the instructions from the Imgur album here.

You’ll need the following:

  1. Gamebit screwdriver
  2. Electrical tape
  3. Wirecutters
  4. Small pliers
  5. Solder Sucker or Desoldering Pump (preferably a heated one like this)
  6. Super Game Boy cartridge
  7. Game Boy cartridge you want to convert
  8. Donor SNES cart shell to fit the completed bits into – PAL or NTSC should both work fine
  9. Stanley Knife/Box Cutter/Scalpel (anything sharp to cut away excess plastic shell in the donor cart)
  10. Any old wire to solder the two PCBs together – I used 10 strand/0.1mm copper equipment wire from Maplins.

The procedure is fairly simply, we need to take both carts apart and solder them together so that they fit in a regular SNES cartridge. Open the Super Game Boy up with the Gamebit and remove the front of the shell. Make a note of which side of the SGB board is facing towards the front of the shell, this is important later when fitting it into the donor cart.

Donor SGB and Pokemon Yellow carts

Pokemon Yellow

Pokemon Yellow connected to SGB cart

The first thing we need to do is get rid of the old cartridge slot that is soldered onto the SGB board – it’s the black bit of plastic in the images below:

Prior to destruction

Prior to destruction 2

There were no clear instructions on how exactly to remove the slot, so I settled for breaking it up with pair of pliers and a bit of force. It’s generally quite brittle plastic because of the age, so the bulk of the plastic will come off easily, but for the last bit (where the slot is attached to the PCB with metal pins) you’ll need to be careful not to damage any of the traces on the board with your pliers. Use the wire cutters to snip the pins away from the plastic as much as possible.

Cart slot removed

View of the reverse

After this is done we need to solder the wires in, but all the metal pins and traces of old solder need to be removed first with the solder sucker – here’s the result after a few holes have been cleaned:

Partially cleaned SGB PCB

You can see what it should look like once all the junk is removed below. Note the scratches on the PCB from excessive force when taking the plastic slot off. I covered these up later with some hot glue and it didn’t cause any problems.

Fully cleaned PCB

Time to get cutting the wires! 32 in total… They need to be long enough to reach round the other side of the cartridge, so cut them about 1.5 times the length of the Gameboy cartridge. Each of them has to have both ends clipped and tinned so that they are easy to work with in the next step. This takes ages, so get comfy…

That’s a lot of wires!

All the wires cut, now time for stripping and tinning:

Stripped wire

Stripped and tinned wire

Once the wires are ready and you’ve given the contacts on the Gameboy PCB a bit of a clean (I use IPA), tin the contacts and line up the carts so that it’s easy to solder them in. Pay attention to the numbers next to the pins on both carts.

Bare PCB’s ready for soldering

Start to solder the wires in on the SGB board, keeping them secure with a bit of electrical tape

Part way through soldering wires

Most of the wires in place

Nearly done…

All wires in place

All wires secured in place

I initially used tape to secure the contacts and wires on the Gameboy board, but switched to hot glue as it was more sturdy. Careful not to put too much on, you need to be able to get the finished product into the shell 🙂

Final state of the GB cart and wiring

Hot glue was also applied to the point where the wires meet the SGB board:

SGB PCB wiring and glue

You might have to tape the Gameboy board to the SGB board to keep it in place, but make sure to put some tape in between the two of them so that the circuits don’t short each other. I also applied an extra bit of tape around both carts to hold everything together (diagonal strip in the picture above).

Finally, get your donor cart and cut out the tabs on the back half of the shell where they stop the SGB board fitting in, making sure that the board is orientated the correct way. I didn’t get a good picture of this, but there is one in the Imgur link at the top of the post. It’s fairly obvious which bits need to be cut out so shouldn’t take long.

Time to test it out!

There are two other modifications that I want to make to this cartridge – correcting the clock speed so that it matches the original Gameboy, and adding a Linkport socket so that you can trade Pokemon between devices. I’ll be covering these in more detail in future posts.


After successfully getting the clock speed fix to work on another Super Gameboy, I applied the same mod to this cartridge. Since I already had the components ready on a prebuilt circuit board, it was a fairly quick process to get this up and running.

Speed fix in progress

Last thing to apply is the label. I ordered mine from, and they look amazing!

Finished product

9 thoughts on “Super Game Boy/Pokemon Yellow SNES Cart

  1. Looks awesome! I like this tutorial better than the imgur one – it’s much more detailed. Seems like a tedious process but I want to try it out.

  2. I wanted to do this for myself but to no success so far,
    I’ve attached all wires and when i put the game in, all i get is the super game boy interface

    • Hi Ama,

      It sounds like the connections between the SGB and Gameboy cartridge aren’t soldered quite right, try checking those – its possible one of the wires might have frayed and snapped off when putting it in the case. Hope that helps, let me know how you get on.


      • thanks for the swift reply, im new at this kind of stuff, how can i easily check this? Id rather not have to desolder and resolder 64 connections again lol

        • Probably easiest to give them a quick visual check for loose connections, then test with a multimeter if that doesn’t indicate anything. I’m assuming you tested the GB cart with your SGB before soldering it together?

          • Yep everything worked prior to trying this!

            also do you use solid wire? I used stranded and just find it a pain to solder

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