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Old 19 July 2019, 21:49   #561
Mick
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With regards to Apple surviving both of my schools (junior/infant and comprehensive) had Apple Macintosh machines, if Commodore could have gotten into the education sector charging insane amounts of money to people with more money than sense then perhaps they would have had the funding to really push R&D.
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Old 19 July 2019, 22:23   #562
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Originally Posted by activist View Post
[...] Hypothetical conjecture, pointless going there again
I only share a piece of the puzzle and I do not pretend to show the whole picture but for sure, it's no "hypothetical conjecture". Simply the reality of the Amiga market in my country at that time period. The Amiga was nowhere professionally speaking, at least officially (not even in schools - but Mac & PC were). For a computer so "ahead" of its time, it always seemed strange to me...
Of course it may have been different in your country.
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Old 20 July 2019, 01:06   #563
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Originally Posted by NorthWay View Post
Wasn't AAA designed for multiple memory layouts? From simple DRAM to multiple VRAM? Something like (at least) 4x difference in bandwidth?
It sure was: there were four versions planned (on paper at least). Ranging from a "single" version with DRAM for chip memory up to a "double" version with VRAM for chip memory. The numbers we've been discussing apply to the fastest of the four, the slowest could not actually display 1280x1024.

Looking back on it now and seeing how many chips they needed for the high end version I do kind of understand why it was scrapped. But the 16 year old in me still wants to see a working version, even though it'll never happen
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Old 20 July 2019, 01:14   #564
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Originally Posted by malko View Post
I only share a piece of the puzzle and I do not pretend to show the whole picture but for sure, it's no "hypothetical conjecture". Simply the reality of the Amiga market in my country at that time period. The Amiga was nowhere professionally speaking, at least officially (not even in schools - but Mac & PC were). For a computer so "ahead" of its time, it always seemed strange to me...
Of course it may have been different in your country.
When I left high school in '86, my school had 3 Amigas for their art and design classes. My A1200 and one of my A3000's came from a university where they were used for audio and video work.
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Old 20 July 2019, 01:28   #565
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Originally Posted by roondar View Post
It sure was: there were four versions planned (on paper at least). Ranging from a "single" version with DRAM for chip memory up to a "double" version with VRAM for chip memory. The numbers we've been discussing apply to the fastest of the four, the slowest could not actually display 1280x1024.

Looking back on it now and seeing how many chips they needed for the high end version I do kind of understand why it was scrapped. But the 16 year old in me still wants to see a working version, even though it'll never happen
Same here, it would be fun to have seen what a dual AAA system would have been capable of. With today's tech, most of the chips could probably be implemented on one or two pieces of silicon. It's too bad that as far as I know the chip designs have been lost.
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Old 20 July 2019, 10:24   #566
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These videos with PS-2 386SX running DOOM is propaganda bullshit.
PS-2 386SX was sold by IBM in 1989 three years before a1200 realease.
386SX from 1992 with SVGA card from 1992 runs better.
Affordble SVGA card from 1992 has few times more bandwith than PS-2.

It was easy to add chunky pixels to AGA but Commodore failde to do it.

c2p? interleaved with other calculations?
Be serious, it is too much work and thats why there are no good 3D games on AGA.

AGA video quality was good enough in 90's and is still good enough.

Problem with AGA is this shit was too slow in 1992 and still is too slow.
AGA should have chunky pixels.

Communism style propaganda of success of some Amiga classic fanatics not change the fact that Commodore banckrupt because AGA has not chunky pixels.
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Old 20 July 2019, 10:38   #567
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Ah! So, there's a conspiracy going on from the AGA illuminaty! Now I see!
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Old 20 July 2019, 11:09   #568
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Originally Posted by swinkamor12 View Post
These videos with PS-2 386SX running DOOM is propaganda bullshit.
PS-2 386SX was sold by IBM in 1989 three years before a1200 realease.
386SX from 1992 with SVGA card from 1992 runs better.
Affordble SVGA card from 1992 has few times more bandwith than PS-2.
I also showed a video of Doom on a 386SX@40MHz and several videos of it on 386DX's, one of which had a VLB SVGA card. Not one of them ran better than the A1200 video Vulture posted.

Suppose I could go on spamming ever more YouTube videos of Doom on the 386 on here. Videos that everyone knows were secretly made by the New World Order to promote the return of the Amiga and the path to world domination. They do give me a lot of money for that stuff, so that's nice.

Oh. S**t. Wasn't supposed to say that...
Nothing to see here, move along!
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Old 20 July 2019, 11:50   #569
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Originally Posted by swinkamor12 View Post
Be serious, it is too much work and thats why there are no good 3D games on AGA.
I enjoyed AB3D. It was an excellent game.
I enjoyed Breathless, it was great fun to play.
I enjoyed Fears, though not as much - and it certainly wasn't the graphics that made it a bad game.

So there's three.
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Old 20 July 2019, 12:06   #570
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Breathless was pretty nice, sadly never played AB3D.

I know it's not as popular and runs terribly on just about everything, but I spend days playing AB3D-II. Didn't even care about the low speed. Some people also rather liked Gloom and Genetic Species.
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Old 20 July 2019, 12:22   #571
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@Dunny:
What about Genetic Species?: http://hol.abime.net/2716
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Old 20 July 2019, 15:21   #572
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Originally Posted by roondar View Post
So, if we give AAA all the advantages in the world we're still only slightly over half way to 400MB/sec

By the way, the document says that the pixel clock and data fetch rate are decoupled: you can have a higher (or lower) clock than the speed of data fetching if desired. I have no clue why they did this, but there it is. Still, it's better than I thought. Does make the following at the start rather strange, though:
Quote:
Originally Posted by AAA docs
The AAA chip bus is an improvement over the ECS and even AA chip bus in terms of memory speed. The AAA chips run a four cycle burst to Chip RAM, which in raw performance is 4.56 times faster than ECS memory access or 1.14 time faster than AA’s two-cycle burst. However, the real key to AAA’s memory architecture is its support for VRAM. With VRAM, display fetches have practically no effect on the normal parallel chip RAM bus, freeing it for use by Blitter, Copper, and CPU.
It's the way VRAM works: At a single read access, a whole row (typically 1024 bits) is copied into an internal buffer, which is then output on the second port with an independent clock, without affecting the normal dram bus. So AAA would have a DRAM bus for CPU and blitter with a quite slow 30 MB/s (1.14 times AGA), but that bus is not used for video refresh, which can use much higher bandwidth for serial data (let's estimate between 160 and 220 MB/s for AAA).

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Originally Posted by roondar View Post
Nevertheless, 600MB/sec is an awful lot for a 1989-1993 design and your calculations showed it to be much less than that, albeit indeed more than I had figured.
Not sure if much less... I forgot that Dave Haynie might have included a DSP with its internal RAM in his calculations, and then his figure is quite credible, even without counting 68040 cache bandwidth . IMHO the total bandwidth is not that absurd for a VRAM based system - it's just that it mainly helps in displaying high resolutions/high color depths, so it's very useful for classic GUI and maybe video applications. The bandwidth to the chipram is the bottleneck here, 30 MB/s is dog slow compared to PS1 or Jaguar which have 3-4x that speed (the Jaguar has to share that with nearly everything else) and is not improved much by using VRAM (just display dma does not eat further into it).

I think AAA would have been rather outdated already in 1994, nice specs but an expensive architecture from the 1980's not well suited for 3D or blitter-based 2D.
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Old 20 July 2019, 16:05   #573
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It's the way VRAM works: At a single read access, a whole row (typically 1024 bits) is copied into an internal buffer, which is then output on the second port with an independent clock, without affecting the normal dram bus. So AAA would have a DRAM bus for CPU and blitter with a quite slow 30 MB/s (1.14 times AGA), but that bus is not used for video refresh, which can use much higher bandwidth for serial data (let's estimate between 160 and 220 MB/s for AAA).
In AAA, VRAM is used as dual ported RAM. There is no separate DRAM for the Blitter and CPU, they also use (the same) VRAM.

Quote:
Not sure if much less... I forgot that Dave Haynie might have included a DSP with its internal RAM in his calculations, and then his figure is quite credible, even without counting 68040 cache bandwidth . IMHO the total bandwidth is not that absurd for a VRAM based system - it's just that it mainly helps in displaying high resolutions/high color depths, so it's very useful for classic GUI and maybe video applications. The bandwidth to the chipram is the bottleneck here, 30 MB/s is dog slow compared to PS1 or Jaguar which have 3-4x that speed (the Jaguar has to share that with nearly everything else) and is not improved much by using VRAM (just display dma does not eat further into it).

I think AAA would have been rather outdated already in 1994, nice specs but an expensive architecture from the 1980's not well suited for 3D or blitter-based 2D.
Your calculations come to slightly over 274MB/sec (assuming 180MB/sec - which seems reasonable considering the 1280x1024 mode was limited to 72Hz). That's nowhere near 600MB/sec.

As for including DSP bandwidth, that is rather strange as AAA does not have one. It does have Mary, but that runs of the same bus as the Blitter, CPU and video.

Again: there were no other systems in 1993 that had bandwidth even remotely close to 600MB/sec. This is especially worth noting as Commodore was limited by the same RAM speeds as everyone else and didn't exactly throw money at AAA.

Anyway, perhaps any further AAA discussion should move elsewhere, it's not really on topic for the A1200.
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Old 20 July 2019, 17:29   #574
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Originally Posted by roondar View Post
But the 16 year old in me still wants to see a working version, even though it'll never happen
Heck yea, I want AAA even as my grumpy old bastard self.
I even tinkered a bit with the Verilog of the Minimig to try to add in a Blipper as AAA does.
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Old 20 July 2019, 18:08   #575
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Originally Posted by roondar View Post
In AAA, VRAM is used as dual ported RAM. There is no separate DRAM for the Blitter and CPU, they also use (the same) VRAM.
Sorry, I think my statement was slightly confusing. VRAM has two ports: The DRAM port (that is addressed like standard DRAM) and a read-only video port. So for CPU and Blitter operations, VRAM and DRAM looks identical, as they only use the DRAM port. For display generation, the graphic chip has to put the row address on the DRAM bus at the right moment and read the data from the video port in sync with the video beam (during the latter one the DRAM bus is free).
Quote:
Originally Posted by roondar View Post
As for including DSP bandwidth, that is rather strange as AAA does not have one. It does have Mary, but that runs of the same bus as the Blitter, CPU and video.
A DSP was not part of AAA, true, but that does not mean it would not have been a part of an AAA Amiga. The DSP in the A3000+ also was not considered to be part of AGA. You're right, that's pure speculation, but again, we do not know what system Haynie was thinking about when making his quote.

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Originally Posted by roondar View Post
Again: there were no other systems in 1993 that had bandwidth even remotely close to 600MB/sec. This is especially worth noting as Commodore was limited by the same RAM speeds as everyone else and didn't exactly throw money at AAA.
Mac Quadra AV 840 from 1993:
https://everymac.com/systems/apple/m...dra_840av.html
About the same VRAM bandwidth as AAA, probably same main memory bandwidth, 66 Mhz DSP (same DSP3210 type as in the A3000+). If you count the bandwidth to the 8k of internal DSP RAM (that's of course debatable, but Haynie might have done so), and assume it can do a longword every clock cycle (very typical for a DSP), you'll arrive at ~500 MB/s total bandwidth. Not counting yet some blitter-like chip that works in VRAM while the CPU is busy (no idea if those Macs had something like that, but probably yes). Again, the distribution of this total bandwidth is very different from the consoles.

I think those Macs are a quite good comparison, as an high-end AAA Amiga probably would have been positioned roughly in the same class as the Quadra AVs. So nothing outlandish about such a bandwidth.

Quote:
Originally Posted by roondar View Post
Anyway, perhaps any further AAA discussion should move elsewhere, it's not really on topic for the A1200.
Yep, but a lot in this thread isn't . After all, I think we're all just discussing some old obsolete systems for our pleasure... But if any mod would move that branch to an own thread, I would not protest.

Last edited by chb; 20 July 2019 at 18:13.
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Old 20 July 2019, 18:26   #576
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I haven't even been able to follow this thread, too many walls of text and loads of technical jargon that make my eyes glaze over.
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Old 20 July 2019, 19:30   #577
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@Dunny:
What about Genetic Species?: http://hol.abime.net/2716
That came out around the time I left the scene, I think. And in any case, I dunno if my usual source of warez would have had it

But as mentioned, there was also Gloom - a fantastic Wolf3D clone, and AB3D-II was also excellent, I remember spending weeks playing that on my 1200+50MHz 030.

To say there were no good 3D games on the Amiga simply because it had no chunky screenmodes is idiotic at best, and a poor troll at that. Games are not suddenly made more fun or more playable that way.
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Old 20 July 2019, 23:22   #578
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AB3D-II was indeed awesome! Could the engine be better optimized? I suppose so, I'm not a programmer. But still, what an incredibly atmospheric game!
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Old 20 July 2019, 23:33   #579
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I suspect that AB3D-II had aspirations beyond what chunky graphics could do at the time - it would have been better suited to graphical acceleration with texture filtering. That it ran at all well on an accelerated A1200 was a testament to the skill behind it.
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Old 21 July 2019, 00:25   #580
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Appologies for snipping parts of your reply, the idea is to make this all somewhat less of a wall of text.
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A DSP was not part of AAA, true, but that does not mean it would not have been a part of an AAA Amiga. The DSP in the A3000+ also was not considered to be part of AGA. You're right, that's pure speculation, but again, we do not know what system Haynie was thinking about when making his quote.
I think we're reading far too much into an off-the-cuff remark made to a receptive audience. It's clear from the AAA documentation you have to bend over backwards to get anywhere near the figure he mentioned. Even when we do so and add a non-existing DSP, we're still nearly 100MB/sec short for the lower end of his range.

Edit: I've been thinking. It's possible that he was talking about theoretical limits - the CPU/Blitter may not have the speed to get to a 400-600MB/sec total, but perhaps the VRAM does support it (if the both ports are used to their theoretical limits). And maybe the BUS theoretically does as well. So if you put in a hypothetical CPU/Blitter combo that can push 200MB/sec or more, you'd actually get to those sort of numbers. But in practice it doesn't matter, since neither the CPU nor Blitter that were to be included could actually support such speeds.

I guess that's my main problem with such figures: having a system with an aggregate of about 70MB/sec of bandwidth to VRAM when using the CPU/Blitter combined and then claiming 400-600MB/sec bandwidth feels wrong to me. Even if it were technically correct (see the first bit of my edit), you'll never be able to actually do anything useful with all that bandwidth other than displaying high resolution still images. This is also were my comments about PSX and PC performance came from: those machines were similarly limited in what they could actually push over the bus, which limited real world performance.
End of edit
Quote:
Mac Quadra AV 840 from 1993
<...>
you'll arrive at ~500 MB/s total bandwidth.
<...>
I think those Macs are a quite good comparison, as an high-end AAA Amiga probably would have been positioned roughly in the same class as the Quadra AVs. So nothing outlandish about such a bandwidth.
I went over the mac Quadra 840AV specs with a fine tooth comb, read up on the DSP etc. That machine does not do 500MB/sec. It does about 300, if you include the internal DSP cache (which I still find highly debatable)*. Which is obviously still a lot, but also only half of what Dave Haynie suggested as the upper limit.

Edit: also see above for reasons why these numbers are essentially useless without comparably quick support hardware (which neither AAA nor the Mac Quadra AV has).

*) VRAM (25MHz@64bit=200MB/sec) + Main RAM/CPU (40MB/sec shared with NuBus) + DSP (66MB/sec) = 306MB/sec.
Quote:
Yep, but a lot in this thread isn't . After all, I think we're all just discussing some old obsolete systems for our pleasure... But if any mod would move that branch to an own thread, I would not protest.
I do like discussing tech stuff like this, but Foebane does have a point - this thread turned from a simple discussion about who liked the A1200 and why to in-depth technical analysis of a non-existent chip set and it's potential competition in the form of the fastest 68K Mac ever made.

So, here's the deal: I'm more than happy to continue this elsewhere - but suggest we do not do it here

Quote:
Originally Posted by vulture View Post
AB3D-II was indeed awesome! Could the engine be better optimized? I suppose so, I'm not a programmer. But still, what an incredibly atmospheric game!
There were some 3rd party patches released for the game that sped it up, so I guess the answer is yes.
Quote:
Originally Posted by Dunny View Post
I suspect that AB3D-II had aspirations beyond what chunky graphics could do at the time - it would have been better suited to graphical acceleration with texture filtering. That it ran at all well on an accelerated A1200 was a testament to the skill behind it.
IIRC, the game won an industry prize for technological achievements at the time.

Last edited by roondar; 21 July 2019 at 13:53. Reason: Added my line of thinking around the usefulnes/uselessnes of bandwidth figures
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