Does anyone have a guide on how to overclock the Mega Drive, because while the concept does interest me the only tutorial I can find is in French and quiet honestly, it is all French to me. And while I could find a link to another tutorial, it appears to have died of link-rot so I could use some help here, does anyone have a copy of an ENGLISH guide? And yes, I googled.
that's not quiet the guide I am looking for, I am looking for a Model 2 guide. Thanks for the help though.
My instructions are applicable to the Model 2. However, just confirm your 68000's pinout. Pin 15 will always be Clock Input, but sometimes Halt is moved to a different pin. You don't even need to sweat a 68K halt switch if you are using a crystal oscillator at a reasonable fixed frequency, like 9-12 MHz.
you can get 10MHz out of MD2... if you go for more, prepared for crayziness (VDP will fail soon). My masterpiece :
Depends heavily on your system's arbiter-- maximum tolerated 68K speed varies from unit to unit. MD1s are universally better at overclocking, though, unless they are the extremely early revisions with a 2-part GLU chip and an EXT port (obvious from lack of TMSS.) Conversely, the best MD1 overclockers I've seen have Motorola or Hitachi CPUs, EXT ports, TMSS, and 1 part GLU. These have exceeded **25 MHz** with only some minor VDP/audio glitches. :D BTW, you can host that image on imageshack.us and post a thumbnail so it doesn't break tables
<!--quoteo(post=193613:date=May 6 2008, 01:38 AM:name=TmEE)--><div class='quotetop'>QUOTE (TmEE @ May 6 2008, 01:38 AM) [/quote] Holy god, that mod is insane! Would you be interested in building a custom one and selling it? I want a tricked out Genesis 3 :o
Have you ever used a Genesis 3? It's the shittiest Genesis model there is. It's full of cheap knockoff hardware, has various issues, and the sound is absolutely horrible. If you want it tricked out, then it should be tricked out with the original hardware parts so it's actually a credible Genesis model.
Tweaker-- full of cheap knockoff parts? It has one ASIC with all the main componentry integrated, including 68K, Z80, VDP, GLU, PSG and YM2612. The only external parts I recall are RAM and analog video/audio hardware. The ASIC is an official Sega part, and works how it should. The sound quality may not be as good because they could've chosen a shitty amp or poorly designed audio path; it's sort of a luck thing if you get a good or bad handful of audio components in an MD2, as well. The real drawback to the Genesis 3 is no expansion port to add a Sega CD, and if you want to use a 32x or Virtua Racing you need to manually connect a couple lines from the ASIC to the cart slot because they just couldn't be bothered to do so. Any hardware that requires one of the reference clocks from the Genesis/MD (VCLK and EDCLK, ~7.67 and 13 MHz) needs that treatment in order to function. As for overclocking a Genesis 3... you really can't. It's all one ASIC, so there's no way to break the clock path to the 68000 and supply your own signal. Unless you'd have the equipment necessary to work at a microscopic level inside an ASIC, which isn't something you'd have at home. So it's better to just grab a model 1 or 2 system.
Now that I think of it, you're probably looking at that french site that copied my guide verbatim and translated it. <_< Without linking back. <_< <_< <_<
Unless you wanted to add more debug items without lag in Sonic games, why would you need an overclock job? It's understandable on Dreamcast and Xbox, but why Genny?
There's slowdown in most games, you just have to be able to recognize it. 3D games are definitely the worst culprits, rarely breaking 5-10 FPS. They're still pretty sluggish past 15 MHz and I had little luck getting them to run properly at over 20 MHz. I'm currently putting together a custom square wave generator to try and get better stability at such extreme speeds.. then maybe such games will be playable
