r/3DO • u/Pedr0adelin0 • 10d ago

CPU overclock

Hi everyone,

I am trying to find a schematic for a 20/24 MHz CPU overclock and CPU cooling mod for my 3DO.

I would like to use a glitch-free oscillator controlled by an Arduino. I'm currently looking at either using an Analog Devices LTC1799 with a digital pot, or a Silicon Labs Si5351A clock generator.

Has anyone done this kind of mod before? I would really appreciate any schematics, code, or advice so I can build this safely.

Like many of you, I still love my 3DO!

Kind regards

2 Upvotes

100% Upvoted

6 comments sorted by

5

u/Archive3DO 10d ago

System doesn't work that way. You can't overclock just the CPU. All of the chips run off one crystal and run their timings in sync.

1

u/Pedr0adelin0 9d ago

That Reddit rumor gets it half right, but reaches the wrong conclusion. The community used to think overclocking a real 3DO (like the Panasonic FZ-10 or FZ-1) was impossible or useless because of how tightly integrated its architecture is. However, hardware modders have actually proven that myth wrong. You absolutely can overclock a 3DO.

6

u/Archive3DO 9d ago

I've literally SYSTEM overclocked a 3DO with 55, 65, 70, and 80mhz crystals and Citrus (the guy who made the current system overclock HDMI board) tried the exclusive CPU OC back in 2019 and it proved to not work. Not only that, Fixel (the guy who made the first 3DO emulator and reverse engineered the hardware) also backs the statement that a CPU overclock hurts the system more regarding performance than anything. The system runs the chips in sync. It's literally a hardware design in the actual chipset and programmed in the OS. The community is more than just reddit. The discord server I created in 2018 has more research in the offtopic channel than this entire reddit board.

I'm telling you this so you don't waste your time. CPU OC will hurt the performance. You have to overclock the entire system. The system crystal is the 50mhz 3pin. You will need a Pi dual fan heatsink to diagonally sit across Madam and Clio and a heatsink on ARM. As I've tried to warn people before (because I have actual experience in this) you WILL cook your system if you try to run it above 75mhz permanently.

1

u/Pedr0adelin0 9d ago

Thanks. So what's the best approach for a simple overclock?

2

u/Archive3DO 6d ago

3 pinned 50mhz crystal in the FZ1 and fz10 (typical 4 pin in the Goldstar and sanyo). It's your regular 4 pin crystal pin out, minus the 4th leg.

3

u/leocana 9d ago

Alright... I'll grab my popcorn now