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Tech and Homebrew => Turbo/PCE Game/Tool Development => Topic started by: djcouchycouch on December 20, 2012, 07:21:00 AM

Title: CPU speeds
Post by: djcouchycouch on December 20, 2012, 07:21:00 AM
I don't remember where, but I read that the PC Engine can be configured to run at various speeds. It can be run up to around 7 mhz, but that most games configured it to run at around 3.5mhz to prevent potential overheating. Did any game actually run at the maximum speed? Is there a real risk to running it that fast?
Title: Re: CPU speeds
Post by: thesteve on December 20, 2012, 07:31:09 AM
i thought most ran at the fast speed
its a jumper in the cart
Title: Re: CPU speeds
Post by: Arkhan on December 20, 2012, 07:39:20 AM
Insanity runs at maximum speeeeeed!

No, there's not a real risk.  You can overclock a 65c02 to upwards of 10mhz without really causing an issue.   I overclocked an Apple IIc.   Same CPU.

Title: Re: CPU speeds
Post by: Black Tiger on December 20, 2012, 08:01:24 AM
All I've ever heard is that virtually all PCE games ran at full speed.

Maybe you're thinking of the SNES and how several games ran at an even slower speed (if you can believe it).
Title: Re: CPU speeds
Post by: djcouchycouch on December 20, 2012, 09:05:33 AM
All I've ever heard is that virtually all PCE games ran at full speed.

Maybe you're thinking of the SNES and how several games ran at an even slower speed (if you can believe it).


Ah, here's where I saw it.

http://en.wikipedia.org/wiki/Hudson_Soft_HuC6280

"The processor operates at three speeds, 1.78 MHz, 3.58 MHz (the speed that most HuCard games run at to avoid overheating the system as the Japanese version of the system was smaller than its North American counterpart) and 7.16 MHz."

Title: Re: CPU speeds
Post by: Black Tiger on December 20, 2012, 09:42:41 AM
All I've ever heard is that virtually all PCE games ran at full speed.

Maybe you're thinking of the SNES and how several games ran at an even slower speed (if you can believe it).


Ah, here's where I saw it.

http://en.wikipedia.org/wiki/Hudson_Soft_HuC6280

"The processor operates at three speeds, 1.78 MHz, 3.58 MHz (the speed that most HuCard games run at to avoid overheating the system as the Japanese version of the system was smaller than its North American counterpart) and 7.16 MHz."




Wow, I guess that otherwise factual wikipedia page was bound to have at least one error. :wink:

If that were actually true, it sure wouod embarrass the Genesis. :P

Although it's not unusual for wiki pages to be full of crap, the PC Engine suffers much worse as it does across the interne, because it wasn't popular in outside of Japan and has many misleading negative stereotypes and rumors.
Title: Re: CPU speeds
Post by: Tatsujin on December 20, 2012, 10:04:14 AM
big lol @ that wiki crap. also because it was smaller than the US counter part. Houly :lol:
Title: Re: CPU speeds
Post by: ccovell on December 20, 2012, 11:13:40 AM
Yeah, that Wiki page is absolute bullcrap.  The 6280 has 2 speeds only: 1.78Mhz and 7.16Mhz.  The 6280 runs at slow speed on power-up, but ALL games immediately set it to high speed.  Slow speed is used "pretty much" only when accessing save RAM (BRAM).
Title: Re: CPU speeds
Post by: nodtveidt on December 21, 2012, 04:41:00 AM
I fixed it. :)
Title: Re: CPU speeds
Post by: esteban on December 22, 2012, 05:20:08 AM
I fixed it. :)


(http://junk.tg-16.com/images/pcg0.html)

Title: Re: CPU speeds
Post by: Arkhan on December 23, 2012, 08:27:58 AM
lol, besides, the HuC/PCEAS startup code fires up high speed mode immediately too. 

Why anyone would want to make a PCE game at retard speed is beyond me.
Title: Re: CPU speeds
Post by: esteban on December 23, 2012, 10:00:31 AM
lol, besides, the HuC/PCEAS startup code fires up high speed mode immediately too. 

Why anyone would want to make a PCE game at retard speed is beyond me.


Jack Nicklaus Golf uses the retard speed exclusively.

AND I ACTUALLY SQUEEZED SOME ENJOYMENT OUT OF THAT GAME (back in the day when poverty was the mother of appreciation).

(http://junk.tg-16.com/images/pcgs.html)
Title: Re: CPU speeds
Post by: SignOfZeta on December 23, 2012, 11:14:02 AM
Was there ANY consumer level CPU in 1987 that was capable of overheating in regular use? Most stuff back then produced more heat from voltage regulators than from processors. Heat sinks and fans were rare.
Title: Re: CPU speeds
Post by: vestcoat on December 23, 2012, 11:26:42 AM
Are you saying I don't need that liquid cooling mod for my TG16?
 #-o
(https://com.com/)
Title: Re: CPU speeds
Post by: nodtveidt on December 24, 2012, 06:38:16 AM
Was there ANY consumer level CPU in 1987 that was capable of overheating in regular use? Most stuff back then produced more heat from voltage regulators than from processors. Heat sinks and fans were rare.
The only example I can think of, and it wasn't a CPU but a video circuit, was the C64... the VIC-II chip had to be heatsinked as it generated a lot of heat. The CPU, however, was always bare. I never really even saw heatsinks on CPUs until the rise of 100MHz 80486 processors.
Title: Re: CPU speeds
Post by: SignOfZeta on December 24, 2012, 07:43:19 AM
My Mac SE (1987) had a big fan in it, but I think that was as much for the power supply, CRT, etc as it was for anything else. The Motorola 68000 in the thing runs bare in Genesis, Neo Geo, etc.

The Capcom CPS2, also 68000 powered, has a great big stupid loud fan in it, but as far as I know the only purpose is to fill the system with a pound of dust. People unhook the fans (so they can hear the game) and they don't melt or anything. I think the actual 68000 in it doesn't even have a heat sync.
Title: Re: CPU speeds
Post by: lukester on December 24, 2012, 12:09:36 PM
Is it true that sounds in a game take up processing speed? I read that somewhere in a transcript of a presentation by Shigeru Miyamoto in 1999.
Title: Re: CPU speeds
Post by: TheOldMan on December 24, 2012, 01:42:05 PM
Yes, it's true. Older systems use more processing power to manage sound, but even on an XBox 360 the cpu has to re-fill the sound buffers, so some processor time is used just for that.
Title: Re: CPU speeds
Post by: Tatsujin on December 24, 2012, 02:11:51 PM
Are you saying I don't need that liquid cooling mod for my TG16?
 #-o
(https://com.com/)


that's quite some steamengine there, punk.
Title: Re: CPU speeds
Post by: Arkhan on December 24, 2012, 05:00:34 PM
Was there ANY consumer level CPU in 1987 that was capable of overheating in regular use? Most stuff back then produced more heat from voltage regulators than from processors. Heat sinks and fans were rare.
The only example I can think of, and it wasn't a CPU but a video circuit, was the C64... the VIC-II chip had to be heatsinked as it generated a lot of heat. The CPU, however, was always bare. I never really even saw heatsinks on CPUs until the rise of 100MHz 80486 processors.

Depends what C64 you look at.

Some heatsink more than just the VIC-II.   Some do the CPU as well, and some even do the SID.

the SID generates heat as well.

That whole f*cking thing generates (read: traps) heat really bad.


It is the leading cause of C64 failure.   Some have cardboard RF shielding that traps heat and fries the chips.  Retards.
Title: Re: CPU speeds
Post by: vestcoat on December 24, 2012, 07:40:17 PM
that's quite some steamengine there, punk.
Google image! I ain't no brown-clad goth, mustache, monocle man.
Title: Re: CPU speeds
Post by: Tatsujin on December 24, 2012, 07:58:04 PM
that's quite some steamengine there, punk.
Google image! I ain't no brown-clad goth, mustache, monocle man.

who's again some of 'em in here?
Title: Re: CPU speeds
Post by: esteban on December 25, 2012, 12:12:42 AM
that's quite some steamengine there, punk.

Google image! I ain't no brown-clad goth, mustache, monocle man.


Hey, that goth is going to grow up into the Monopoly Man (or Mr. Peanut), so spread a little love to the goths. (http://junk.tg-16.com/images/pcg0.html)

Title: Re: CPU speeds
Post by: vestcoat on December 25, 2012, 02:17:38 PM
Traditional goth dorks in black are fine, but the brown-ies have been led astray.
Title: Re: CPU speeds
Post by: Tatsujin on December 25, 2012, 02:31:49 PM
'IT'S THE MIND'
Title: Re: CPU speeds
Post by: esteban on December 26, 2012, 10:35:17 AM
'IT'S THE MIND'

"Know what I mean? Nudge. Nudge."
Title: Re: CPU speeds
Post by: vestcoat on December 29, 2012, 10:51:10 AM
Say no more!
Title: Re: CPU speeds
Post by: Tatsujin on December 29, 2012, 03:47:55 PM
I have that terrible feeling of déjà vu.
Title: Re: CPU speeds
Post by: HercTNT on December 29, 2012, 10:12:53 PM
Was there ANY consumer level CPU in 1987 that was capable of overheating in regular use? Most stuff back then produced more heat from voltage regulators than from processors. Heat sinks and fans were rare.
The only example I can think of, and it wasn't a CPU but a video circuit, was the C64... the VIC-II chip had to be heatsinked as it generated a lot of heat. The CPU, however, was always bare. I never really even saw heatsinks on CPUs until the rise of 100MHz 80486 processors.

Depends what C64 you look at.

Some heatsink more than just the VIC-II.   Some do the CPU as well, and some even do the SID.

the SID generates heat as well.

That whole f*cking thing generates (read: traps) heat really bad.


It is the leading cause of C64 failure.   Some have cardboard RF shielding that traps heat and fries the chips.  Retards.

I'm the overcautious type i tend to buy tiny bga heatsinks for video card memory and use them to heatsink they shit outta everything. i will heatsink mosfets, voltage regulators, chipsets etc if a system is known to have heat issues. Hell, my dingoo a320 has a copper heat spreader on the cpu has its always overclocked (most likely only added weight to the system). I overclocked my genny to 10mhz and threw a heatsink on that as well (i now know thats overkill to).
Title: Re: CPU speeds
Post by: Marll on January 04, 2013, 04:15:50 AM
How does one go about overclocking one of these older systems like a Genesis or TG? I've been overclocking PCs ever since a viable BIOS in a system allowed it, and tend to also heatsink or watercool in some fashion everything in a PC. I've always wondered if heatsinking and cooling older systems would have any benefit at all.

Also would OCing something like a Genesis make all the games run faster, such that the audio is all weird too?
Title: Re: CPU speeds
Post by: ccovell on January 04, 2013, 12:27:25 PM
Also would OCing something like a Genesis make all the games run faster, such that the audio is all weird too?

The Genesis can be overclocked up to ~10Mhz without any graphical or sound glitches, but the TG and NES have their sound devices in-CPU which is why their sound goes all weird when overclocked.
Title: Re: CPU speeds
Post by: Arkhan on January 05, 2013, 09:37:09 AM
How does one go about overclocking one of these older systems like a Genesis or TG? I've been overclocking PCs ever since a viable BIOS in a system allowed it, and tend to also heatsink or watercool in some fashion everything in a PC. I've always wondered if heatsinking and cooling older systems would have any benefit at all.

Also would OCing something like a Genesis make all the games run faster, such that the audio is all weird too?


There's a pretty simple mod you can do to overclock the Genesis.  You basically just use a new oscillator and feed it into the CPU.   It's extremely simple to do, even if you're completely new to soldering/fiddling around.

I had to help someone fix their botched mod recently.   They wired it to the z80 instead of the 68000.   Whoops, lol.

I never saw the honest point to overclocking a console.   A computer (like an Amiga or Apple II or something), I can see it being useful, but I don't recall the list of Genesis games that really benefit from this mod being that large. 


Title: Re: CPU speeds
Post by: Black Tiger on January 05, 2013, 10:16:33 AM
How does one go about overclocking one of these older systems like a Genesis or TG? I've been overclocking PCs ever since a viable BIOS in a system allowed it, and tend to also heatsink or watercool in some fashion everything in a PC. I've always wondered if heatsinking and cooling older systems would have any benefit at all.

Also would OCing something like a Genesis make all the games run faster, such that the audio is all weird too?



There's a pretty simple mod you can do to overclock the Genesis.  You basically just use a new oscillator and feed it into the CPU.   It's extremely simple to do, even if you're completely new to soldering/fiddling around.

I had to help someone fix their botched mod recently.   They wired it to the z80 instead of the 68000.   Whoops, lol.

I never saw the honest point to overclocking a console.   A computer (like an Amiga or Apple II or something), I can see it being useful, but I don't recall the list of Genesis games that really benefit from this mod being that large. 






http://www.sega-16.com/forum/showthread.php?22854-Annotated-list-of-compatible-games-for-overclocked-Genesis-Mega-Drive
Title: Re: CPU speeds
Post by: HercTNT on January 05, 2013, 01:01:20 PM
Overclocking the genny has very tangible benefits as per the list that black tiger was kind enough to post. it does have its drawbacks though. 32x does not work well if at all with an overclocked genny. have heard it can cause problems with the cd addon as well at times. otherwise, it makes alot of games run much smoother without audio distortion. best way to do the mod is include a switch that allows changing between clock speeds incase some games do not play well.
Title: Re: CPU speeds
Post by: Black Tiger on January 06, 2013, 07:29:51 AM
Its not worth doing to your main playing setup, but neat to fool around with overclocked games on a second system. Kinda like messing around in games using a game genie.
Title: Re: CPU speeds
Post by: Vecanti on January 06, 2013, 08:26:04 AM
http://www.sega-16.com/forum/showthread.php?22854-Annotated-list-of-compatible-games-for-overclocked-Genesis-Mega-Drive


That list must be for the machines that don't have "Blast Processing" built in?


Title: Re: CPU speeds
Post by: HercTNT on January 06, 2013, 10:58:16 AM
Its not worth doing to your main playing setup, but neat to fool around with overclocked games on a second system. Kinda like messing around in games using a game genie.

Agreed, i did this to a very beatup unit that i still use. My opinion the only reason to do this mod is if your gonna put in a switch. being overclocked all the time caused problems with some games. Its like my original gameboy. I have it overclocked on a switch. Native speed is 4.1, overclocked is 6mhz. Its way to much, i'm gonna replace the secondary clock crystal with a 4.5 one for a much milder overclock. just like the genny, there are a few games that benefit greatly from alittle more speed.