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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: McVenco on October 31, 2006, 07:37:14 AM

Title: Is there any use for a PPC with just classic AmigaOS?
Post by: McVenco on October 31, 2006, 07:37:14 AM
My question is as the topic title says: I've got a BPPC/040 card, and OS 3.9. Until now I'm not quite sure in what point a PPC processor can be of any help to the classic AmigaOS.

What I want to do with my A1200 is just play around with a lot of classic OS programs, connect to the internet, maybe play some mp3s and DVD's and figuring out a bit of programming for OS 3.9.

Am I right when I think that for this use I'd be better off with a 68060 and no PPC, rather than a PPC+68040?

I want to upgrade to a tower in the future, and add a PCI graphics card, so I wouldn't need the BPPC for a BVision either I presume.

What are your thoughts on this?
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: Effy on October 31, 2006, 07:47:13 AM
Keeping the BPPC and go for pci cards is a way to go. Also don't forget that several datatypes are coded for PPC use and therefor are much faster than an 68060 !! For classic use of older AGA or OCS games a BPPC will indeed be sitting waiting for work to do but I guess for internet use it will be more than fast enough  :-)
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: keropi on October 31, 2006, 07:53:36 AM
with 3.x OS , the ppc can be used to free the 68k on the following tasks for example:
- picture datatypes
- mp3 decoding / encoding
- movie playback
- archiving (there is LHA_WOS)
- many ppc specific progs/games that need warpOS/powerUP , see aminet...

actually see the ppc as a faster 68k helper cpu...
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: zipper on October 31, 2006, 08:44:21 AM
Especially bigger pictures on deeper screens are so laborious to handle without a PPC processor. The difference even with a 060 is huge.
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: McVenco on October 31, 2006, 09:25:04 AM
Alright, this certainly clears up a lot. If a 68060 had been better I would be looking for a trade, but let's forget that then :-D

Another question then: is worthwhile to look for a BVision, or will a decent PCI card work just as good?
I've got a GeForce Ti4200 in my current pc, would that work correctly with a Mediator or G-Rex busboard?
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: humppa on October 31, 2006, 09:26:50 AM
Get a BVision or try to find a GRex with nice PCI-cards and install Morphos Powerup (unfortunately, Mediator is not supported by MOS).
In OS 3.9 your PPC is getting really bored after some time - on MOS it has much more to do and there is no speed-loss "thanks" to context-switching.
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: McVenco on October 31, 2006, 09:46:41 AM
I don't want to switch to MorphOS (at least not yet), I first want to see what I can achieve with the classic OS.

Maybe in the near or far future I will check out other OSes like MorphOS/AROS/OS4, but as for now I really want to stick with the classic AmigaOS, that's why I wanted to know the value of a PPC processor combined with it.
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: humppa on October 31, 2006, 10:11:23 AM
Quote
I don't want to switch to MorphOS (at least not yet), I first want to see what I can achieve with the classic OS.


You don't have to completely switch - just set up a dual-boot system and you are free to choose.
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: AmigaMance on October 31, 2006, 04:49:19 PM
Quote
on MOS there is no speed-loss

 Sorry, i have done many tests on this and i don't confirm it. WarpOS apps still run faster on my AOS installation.
Edit: Or at the same speed, best case.
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: Craven1200 on October 31, 2006, 05:11:32 PM
Quote

McVenco wrote:
I've got a GeForce Ti4200 in my current pc, would that work correctly with a Mediator or G-Rex busboard?


afaik  there is no support for nvida chipsets only:

Voodoo3/4/5
S3 Virge /DX
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: Piru on October 31, 2006, 05:21:36 PM
@AmigaMance

Run WarpUP-WarpOS/Demos/pixelOmania both under MOS and AOS. The speed difference should be evident.
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: AmigaMance on October 31, 2006, 05:51:34 PM
Well, i just did ran it and the difference is profound, but i still don't understand why you suggested this. Pixelomania is just a demo that (quoting from its output message) "Measures the performance of CPU context switches". It's obvious that there are NO CPU switches in MorphOS and that wasn't the point of my previous post.
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: Piru on October 31, 2006, 05:55:12 PM
@AmigaMance
From humppa's post:
Quote
on MOS there is no speed-loss "thanks" to context-switching.


Well, what was the point then?
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: AmigaMance on October 31, 2006, 06:13:19 PM
@ Piru
 I will just quote my previous post. I think it's clear enough: :-)

Quote
Quote
on MOS there is no speed-loss

 Sorry, i have done many tests on this and i don't confirm it. WarpOS apps still run faster on my AOS installation.
Edit: Or at the same speed, best case.


Edit: Ok, just to clarify: I'm talking about real-life apps, not about a cpu context-switching test and i didn't mention anything about context-switching. Humppa did. :-)

Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: Piru on October 31, 2006, 06:25:46 PM
@AmigaMance
Quote
i'm not mentioning anything about context-switching. Hummpa did.

Well, that's quite obvious. What I am wondering is why you quoted him while he was talking about something else.

Anyway, at least while I was still using my A1200, most WOS apps were clearly faster under MOS. Much of that was due to fully PPC native CGX and other OS components vs slower 68K counterparts under AOS. And this was with 060 BPPC, even.

However, if you have some WOS app that deliberately tries to avoid context swithces, it can then happen that it is marginally faster under AOS 3.x (since under AOS the PPC chip is 100% free for the app, while under MOS it also runs other parts of the OS). Regardless, I'm confident in claiming that MOS WOS emu beats the original in most cases, and it's less buggy, too... ;-)
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: CLS2086 on October 31, 2006, 08:55:04 PM
The master Piru has spoken  ;-) .

The only good point for AOS3.x it's the custom OCS/ECS/AGA chip use.
Title: Re: Is there any use for a PPC with just classic AmigaOS?
Post by: Karlos on October 31, 2006, 09:01:32 PM
Well-written OS3.x/WarpOS (or PowerUP) software is not context switch heavy, so the whole context switch overhead issue ought to be largely irrelavent.

A PPC with OS3.x gives a much needed boost to a lot of computationally intensive operations, such as datatype decoding, image dithering (3.9 picture.datatype), mp3 playback and of course any games written to take advantage of it.

With MOS installed, you get to run your 68K/RTG apps faster than the real 680x0 could manage (especially the 040).

Overall, I'd say, yes, there is a point. Using the second 1200T here that has an 040+mediator, the difference provided by the PPC for the common tasks (datatype stuff) is readily apparent.