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MOFO – The Ultimate Dual Clock Mod for Sony PlayStation

Introducing the MOFO – Multi Output Frequency Oscillator dual clock mod for Sony PlayStation. A DFO, MFO & PAL60 mod in one.

The multi output frequency oscillator (MOFO) is a dual clock mod for the Sony PlayStation that provides a switchable PAL/NTSC GPU clock and PAL/NTSC RGB Encoder subcarrier clock, as well as a fixed subcarrier clock for PAL60 operation.

It is based on both the Dual Frequency Oscillator and Multi Frequency Oscillator mods with the addition of a PAL60 output.

Composite Video and Single Format TV’s

One reason I wanted to design this mod is because I own a single format PAL CRT TV and have been wanting to play Silent Hill in 60Hz via composite video. This results in a black and white image so I would be forced to use RGB or play in 50Hz. Neither of which appeals to me for Silent Hill. 60Hz for obvious reasons. But why composite video?

Composite Video and the Pixel Blending Effect

Silent Hill is one of those games that looks quite bad in anything other than composite video. This is because the game relies heavily on dithering to create the fog effect. In both RGB and any upscaled HDMI mods, this looks wrong. Via composite video the fog benefits from the blending effect where the pixels all blend together to produce the intended effect the developers wanted.

This video has a good example of how this works.

So I designed the MOFO to get a nice PAL60 signal to work with my PAL only TV. I can now enjoy Silent Hill in both 60Hz and with correct fog effect.

As you can see by the screenshot, this is a 60Hz image, in colour, and with the correct fog effect over composite video. Thanks to the MOFO’s SUB-B clock output, I get a PAL60 signal which my PAL only CRT TV can now understand.

PAL60 & Composite Video Dot Crawl

PAL60 will be prone to the same problems as any standalone PAL60 mod such as dot crawl. The MOFO does not eliminate dot crawl, it is simply a convenient way to generate a PAL60 signal for those that require this mod. However, this may be more in sync and less problematic than standalone PAL60 mods because the GPU clock and the subcarrier clock are at least derived from the same clock source.

What is the difference between a DFO, MFO, and MOFO?

  • The Dual Frequency Oscillator (DFO) provides an auto switching GPU clock output.
  • The Multi Frequency Oscillator (MFO) provides an auto switching GPU clock output and an auto switching subcarrier clock output.
  • The Multi Output Frequency Oscillator (MOFO) provides an auto switching GPU clock output, an auto switching subcarrier clock output, and an additional fixed subcarrier clock output.

The MOFO is an updated version of the MFO which itself was an updated version of the DFO.


The PlayStation MOFO is available to download from

The PlayStation MOFO is available to buy from


Micro for creating the original Dual Frequency Oscillator (DFO) and immerhax/Skum for creating the Multi Frequency Oscillator (MFO).


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