PSOne Overclocking

Post by **Skyone** » Thu Aug 10, 2006 5:27 am

Due to request, I've whipped up a tutorial on how you can overclock the Playstation [One].

http://skytroniks.com/index.php?i=projects&p=psoneoc

Tell me what you think of it and hopefully if you have an extra psone lying around, you can try it out and tell us how it goes.

Confirmed clock speeds:
-80 MHz

-Skyler

scherzo · Post by **scherzo** » Thu Aug 10, 2006 7:34 am

I'd like to see it but you posted a bad link.

Post by **Skyone** » Thu Aug 10, 2006 5:28 pm

scherzo wrote:I'd like to see it but you posted a bad link.

You sure?

If it still doesn't work for you, go to http://skytroniks.com/ click projects and the psone overclocking.

Krepticor · Post by **Krepticor** » Thu Aug 10, 2006 5:42 pm

ok now I did experience delays on the psone one Castlevana: SOTN
(usually after a boss)

anyway overclocking the psone what heating problems need to be considered?

Post by **Skyone** » Thu Aug 10, 2006 5:58 pm

Amazing, there are no heating problems at 40 MHz.

Krepticor · Post by **Krepticor** » Thu Aug 10, 2006 6:02 pm

and at 80?

Post by **Skyone** » Thu Aug 10, 2006 6:45 pm

Krepticor wrote:and at 80?

Ya, what I meant was 80 MHz divided by 2 (PLL) = 40 MHz at which the CPU runs at. So ya, 80 MHz.

Krepticor · Post by **Krepticor** » Thu Aug 10, 2006 8:09 pm

the big chip doesn't even get a little warm?

Post by **Skyone** » Thu Aug 10, 2006 8:10 pm

Krepticor wrote:the big chip doesn't even get a little warm?

Mmmmm, nope.

Krepticor · Post by **Krepticor** » Thu Aug 10, 2006 8:21 pm

Sweet!

What is the standard clock? 40 Mhz?

If so why not try tripling it at 120 MHz? That way the psone and the n64 could have a triple clock!

atari2600a · Post by **atari2600a** » Thu Aug 10, 2006 8:50 pm

Any side-affects like on older systems? (NES+overclocking=higher sound)

Post by **Skyone** » Thu Aug 10, 2006 8:57 pm

atari2600a wrote:Any side-affects like on older systems? (NES+overclocking=higher sound)

Nope, no side effects.

Krepticor, lemme explain.

If you open the PSOne, there is a chip oscillator (PLL Chip). The is called the stock (original) clock. It is rated at ~67 MHz. That is directly feeded into the CPU. The CPU divides the speed by 2. So the final speed the CPU runs at is ~33 MHz.

Now we replace that ~67 MHz with 80 MHz. We feed that into the CPU which divides the 80 MHz by 2, giving us 40 MHz.

So in theory, we're replacing the 33 MHz which the CPU runs with 40 MHz. (67 MHz with 80 MHz).

Get it?

MM007 · Post by **MM007** » Fri Aug 11, 2006 11:30 am

The 33.86MHz to 40 MHz boost is a gain of 6.14 MHz, so it not getting hot is understandable. There is less than a 20% gain, but it is still a fairly nice one as overclocking percentages go.

I've gotten less percentage overclock for more performance on a PC, but that's apples and oranges, I suppose.

Also, I am wondering: Have you tried using this new clock on any other chips that may use the same clock as the CPU, or is the 33MHz clock only connected to the CPU to begin with anyway? The fact that you have to remove sever the same electrical connection in two places (The CPU and the clock pin) makes little sense to me unless there are other factors involved.

Post by **Skyone** » Fri Aug 11, 2006 3:31 pm

It's weird because I have no clue how exactly the clock gets to the other components. I'm guessing the PLL actually outputs a series of clock speed and sends it out to various components, so putting the 80 MHz on other components would not only be useless but may be harmful because the other components may runs on speeds higher than 80/40 MHz.

Krepticor · Post by **Krepticor** » Fri Aug 11, 2006 4:21 pm

ok I understand now but my issue was I thought the clock had to be set at in interval that was divisible by the original clock?

so the 40Hz boost versus the 33Mhz doesn't have anything that runs different?

I say this since the SNES overclock has a problem for the sprites jumping over the screen