Overclock your Super Nintendo/Super Famicom

From Wiki-Scene

NOTE:This guide does not apply to the miniature SNES/SFC. The mini SNES contains a combo chip that houses the CPU and both PPUs. There is only one clock input and overclocking this chip would cause the PPU's clock to rise, resulting in the rise of the refresh rate to your TV; 50 Hz PAL or 60 Hz NTSC. This will make it incompatible with most standard TVs of your region.

If you are unaware as to what overclocking accomplishes, please see the overclocking page.

Tools you will need:

9.5 mm security bit (to open SNES)
x-acto knife
soldering iron and solder
crystal oscillator

Now that we have what we need, you need to open the SNES to where you are looking at the motherboard. There are 2 parts of the board you will be dealing with: the CPU , and the voltage regulator (located on the left-rear behind the cartridge port). Below is a picture of where the CPU is located.

Some information on the SNES's CPU:

This CPU is manufactured by Ricoh, and is a modified version of the WDC 65c816 that runs at a maximum speed of 3.58 MHz (software selectable multiplier). The SNES's CPU internally divides whatever clock it recieves by 6, in this case, it recieves a 21.477 MHz clock signal. What you will need to do is disconnect the 21 MHz signal, and connect a 31 MHz (or anything higher that 21.477 MHz) crystal oscillator resulting in a maximum speed of 5.1 MHz.

Pin 48 of the Ricoh 5A22 CPU

Step 1: You will need to disconnect the CPU's clock pin from the board; this is pin 48.

This can be tricky to do, you will definitely need to have some robust soldering skills, and a roll of desoldering wick (in case you bridge some pins in solder). The easiest way to do this is to press your soldering iron at the base of pin 48, and then use the xacto knife to CAREFULLY raise the pin. These pins are very fragile, and breaking this pin will render the SNES useless!

Step 2:Now connect your crystal oscillator to a +5V power source, and suitable ground. You can pull +5V from the voltage regulator's output pin. looking at the front of the regulator, this is the pin on the far right (unit has 3 pins).

Step 3, clock pin connection: Once you've checked to make sure your oscillator has a good power source, we will run a wire from the clock output pin on the oscillator, to pin 48 on the CPU.

Now power on and test, you should have an overclocked Super Nintendo.

The SNES's CPU is pretty resilient to overclocking; up to 2x the stock speed. Unfortunately the other components on the board do not like the CPU running too high out of spec. Below are the following speeds that have been tested and the results that were experienced. NOTE: Results always vary depending on each individual system's threshhold.