Welcome to UCM's Super Nintendo overclocking guide! It has taken me a while, but I have finally managed to overclocked the SNES's CPU. Before we begin, there are a few tools you will need to perform this mod.

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 we 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.

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). We will be going by the maximum speed for sake of confusion ;). The SNES's cpu internally divides whatever clock it recieves by 6, in this case, it recieves a 21.477 MHz clock signal. What we are going to do is disconnect the 21 MHz signal, and connect a 31 MHz crystal oscillator resulting in a maximum speed of 5.1 MHz! Quite a speed boost!

We will need to disconnect the CPU's clock pin from the board; this is pin 48 (see below).

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!

Now we need to connect our 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). I usually connect my ground to a screw that hold the RF shielding on. below is a chart of how your oscillator should be wired.

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. NOTE:5.1 MHZ IS GLITCHY. I AM IN NEED OF SOME OSCILLATORS BETWEEN THE SPEEDS OF 23 AND 25 MHZ. ANYONE WILLING TO DONATE CAN CONTACT ME, ROBERT IVY. I WILL BE SURE TO ADD YOU TO THIS PAGE, AS YOU WILL BE AN IMPORTANT PART OF SNES OVERCLOCKING DEVELOPMENT. THANKS!

Link is scattered all over the screen ;).

This page is (c) 2006 Underground Console Mods and Robert Ivy. it cannot be copied or distributed without my permission.