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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: barney on August 19, 2009, 11:39:01 PM

Title: When is an FPU chip really needed????
Post by: barney on August 19, 2009, 11:39:01 PM
Hello, I have an Amiga 1200 with an accelerator board.   Do I necessarily need the FPU chip installed?  How often and why is it really needed?  Will I see a difference in every days gaming?  Just wondering whether this was a necessary upgrade or not.

Thanks.

Barney
Title: Re: When is an FPU chip really needed????
Post by: TheGoose on August 19, 2009, 11:44:27 PM
Not in most gaming. Most games do not make use of FPUs. Some later 3D games will - Doom, Quake, etc.
Title: Re: When is an FPU chip really needed????
Post by: Karlos on August 19, 2009, 11:47:52 PM
Unless you want to do floating point arithmetic, you can live happily without it. Very few amiga games ever used an FPU. Those that did were usually 3D and used it for polygon calculations. The amiga version(s) of Quake is just about the only example I can think of that requires an FPU to work at all. And frankly, to play that, the FPU needs to be inside a fast 68060 ;)

So in short, no, you really don't need it.

-edit-

@TheGoose

As far as I can recall, Doom used fixed point arithmetic.
Title: Re: When is an FPU chip really needed????
Post by: F1Lupo on August 20, 2009, 12:15:05 AM
heavily used in 3d rendering programs like lightwave & others
Title: Re: When is an FPU chip really needed????
Post by: NovaCoder on August 20, 2009, 12:24:47 AM
this will give your FPU a good workout (http://pouet.net/prod.php?which=52968)

:)
Title: Re: When is an FPU chip really needed????
Post by: barney on August 20, 2009, 12:28:13 AM
Thanks for the info everybody.  I guess I really don't need one after all.

Barney
Title: Re: When is an FPU chip really needed????
Post by: ChaosLord on August 20, 2009, 03:42:37 AM
99% of Amiga games never use FPU at all.

Total Chaos AGA uses an FPU if you have one, but only once, the very first time you run the game, to decompress all the audio into Amiga format.  If you have an 060 FPU this takes 6 minutes.  If you have no FPU it takes 1-3 hours.
Title: Re: When is an FPU chip really needed????
Post by: rkauer on August 20, 2009, 06:10:00 AM
IIRC, TFX (war planes simulation) uses the FPU, too.

 Anyway, even with with a 68882 @50MHz the game was dog-slow.
Title: Re: When is an FPU chip really needed????
Post by: NovaCoder on August 20, 2009, 06:13:39 AM
There a few different versions of TFX floating around with various patches applied.  If by some miracle you happen upon the right combination you might get some decent speed out of it............if you have an 060 that is ;)
Title: Re: When is an FPU chip really needed????
Post by: BozzerBigD on June 19, 2017, 01:25:07 PM
@NovaCoder

Which version of TFX do you recommend for the 060?
Title: Re: When is an FPU chip really needed????
Post by: TCMSLP on June 19, 2017, 02:39:59 PM
I'm often finding software that either needs (or benefits from) FPU.  I remember having to download specific non-FPU versions of AmigaAMP (or was it AmiAmp?), video players, some compression utilities etc - all day to day stuff really.  

As far as games go - as others have already said, the later 3D games will likely need (or massively benefit) from an FPU;  I'm thinking Alien Breed 3D, the later Doom ports etc.   It won't make any difference to the vast majority of games though :)
Title: Re: When is an FPU chip really needed????
Post by: BozzerBigD on June 19, 2017, 02:46:10 PM
@TCMSLP

Because of the way that Doom and Alien Breed 3D use a kind of 2.5D tech rather than full polygon 3D, a FPU isn't necessary. Quake is the first FPS that required a FPU and also Tales from Heaven a full 3D platformer probably requires a FPU (and a 060 where it's built in).
Title: Re: When is an FPU chip really needed????
Post by: Rob on June 19, 2017, 02:56:14 PM
Quote from: BozzerBigD;827327
@NovaCoder

Which version of TFX do you recommend for the 060?


Charlie Wallace released updated binaries for TFX so it would be best to try those out.  If the 040 version still doesn't run on your 060 setup try and track down Oxypatcher to speed up the 030 FPU version.

http://hol.abime.net/1367
Title: Re: When is an FPU chip really needed????
Post by: BozzerBigD on June 19, 2017, 03:09:09 PM
@Rob

Thanks! ;-)
Title: Re: When is an FPU chip really needed????
Post by: kolla on June 19, 2017, 03:32:20 PM
A search on Aminet for packages that contain files with name that either contain 68881, 68882 or FPU gives you a hint about the ammount of software that benefit from FPU, if not require it.

I am actually surprised by the number of games showing up...

http://aminet.net/search?content=68882&content=68881&content=fpu

In addition there is a lot of software buildt for 040 and 060 where FPU is not mentioned explicitly, but is taken for granted. Also in addition is software using math libraries that are optimized for FPU. And of course commercial software that is not on Aminet.
Title: Re: When is an FPU chip really needed????
Post by: TCMSLP on June 19, 2017, 04:07:36 PM
Quote from: kolla;827335

In addition there is a lot of software buildt for 040 and 060 where FPU is not mentioned explicitly, but is taken for granted. Also in addition is software using math libraries that are optimized for FPU. And of course commercial software that is not on Aminet.


Ah yes - I remember a heap of datatypes being available in FPU/NonFPU version too :)
Title: Re: When is an FPU chip really needed????
Post by: wiser3 on June 19, 2017, 07:09:21 PM
The Astronomy programs Distant Suns and Digital Universe don't require FPU's but will use it if available. Having the FPU makes a very noticeable difference.
Title: Re: When is an FPU chip really needed????
Post by: guest11527 on June 19, 2017, 07:22:55 PM
Quote from: kolla;827335
A search on Aminet for packages that contain files with name that either contain 68881, 68882 or FPU gives you a hint about the ammount of software that benefit from FPU, if not require it.

Ok, so let's see. This search results in 178 packages of a total 81912 packages, which are about 0.2%. Ok, that's probably not accurate, let's even make this 1%. It's still a minority that really requires it. Having a FPU is probably nice, but not really required.

For development, a MMU is considerably more useful, but again, if you just look at the statistics, it's hard to guess how many developers are really left that would profit.
Title: Re: When is an FPU chip really needed????
Post by: Niding on June 19, 2017, 08:23:22 PM
Quote from: Thomas Richter;827340
Ok, so let's see. This search results in 178 packages of a total 81912 packages, which are about 0.2%. Ok, that's probably not accurate, let's even make this 1%. It's still a minority that really requires it. Having a FPU is probably nice, but not really required.

For development, a MMU is considerably more useful, but again, if you just look at the statistics, it's hard to guess how many developers are really left that would profit.


http://aminet.net/package/mus/play/Eagleplayer_2.05

Shows up, and doesnt require FPU. I realise you said "benefit", but that was just a instant pick since I got that player on my Amigas.

That said, intresting commentaries from Thomas Richter.
Title: Re: When is an FPU chip really needed????
Post by: UberFreak on June 19, 2017, 08:29:19 PM
Quick answer: over 90% of demo-scene productions created since the late 90's, when 040 and 060 became the standard in competitions.
If you want to enjoy the best today's demo-scene has to offer, you need an (overclocked) 060.

The "standard" compo-machine in the biggest scene event in recent years (Revision party in Germany) is an AGA Amiga with 060 CPU running at 66Mhz.
Everything created for this setup freely assumes an FPU is available.
Title: Re: When is an FPU chip really needed????
Post by: guest11527 on June 19, 2017, 08:57:47 PM
Quote from: UberFreak;827342
The "standard" compo-machine in the biggest scene event in recent years (Revision party in Germany) is an AGA Amiga with 060 CPU running at 66Mhz.
Everything created for this setup freely assumes an FPU is available.

Did I ever say that I do not understand this stuff? Frankly, if I want to get the most of a machine, I'll get a PC. If the competition is to get the most out of as little as possible, stick with a plain 68K at 7MHz and get creative. That is the art. Heck, even a 1.7Mhz 6502 can do interesting things if you know how to play it.
Title: Re: When is an FPU chip really needed????
Post by: BozzerBigD on June 19, 2017, 09:01:59 PM
@UberFreak

That's not a compelling argument for the Vampire getting a FPU ASAP (or a Classic user to upgrade to be honest) as most 'regular' users will just check out Amiga demos on YouTube if that scene interests them!
Title: Re: When is an FPU chip really needed????
Post by: Iggy on June 19, 2017, 09:26:06 PM
Quote from: Thomas Richter;827343
Did I ever say that I do not understand this stuff? Frankly, if I want to get the most of a machine, I'll get a PC. If the competition is to get the most out of as little as possible, stick with a plain 68K at 7MHz and get creative. That is the art. Heck, even a 1.7Mhz 6502 can do interesting things if you know how to play it.


Or slower, if you look at some of the C64 demos, but we are still talking about Amigas here, and there is no one standard for them.
Sure, '040 and '60 cpus MAY be an unfair comparisons, but they are more common than 1.7 MHz C64s (without taking the C128 into account).

As to PCs, to each his own, but the point of a demo is what you can do within the constraints of specific hardware, and a demo on a PC should be MORE impressive than on something less capable.
Title: Re: When is an FPU chip really needed????
Post by: Oldsmobile_Mike on June 19, 2017, 10:03:10 PM
Quote from: Iggy;827345
1.7 MHz C64s

C64 ran at 1.0MHz.  Actually I think it was 1.02MHz, or something like that (6510 vs 6502), but now we're just splitting hairs.  :lol:
Title: Re: When is an FPU chip really needed????
Post by: UberFreak on June 19, 2017, 10:04:00 PM
No argument from me.
The most innovative stuff comes from the C64 scene, which is the only one I'm semi-active in.
I also agree with sticking with A500 specs. If you check last Revision's results, you'll see A500 demos are making a serious comeback :)

AGA/060 demos can be compared to early Pentium-1 demos.
Many (Most?) of them are "just" C2P based and can be easily ported to other platforms (as proven by Atari Falcon ports of TBL demos).
Still, I enjoy watching the ones that run at acceptable speed on a 50Mhz 060 and don't require overclocking (Hi, Elude...).

Quote from: Thomas Richter;827343
Did I ever say that I do not understand this stuff? Frankly, if I want to get the most of a machine, I'll get a PC. If the competition is to get the most out of as little as possible, stick with a plain 68K at 7MHz and get creative. That is the art. Heck, even a 1.7Mhz 6502 can do interesting things if you know how to play it.
Title: Re: When is an FPU chip really needed????
Post by: UberFreak on June 19, 2017, 10:09:22 PM
Quote from: BozzerBigD;827344
That's not a compelling argument for the Vampire getting a FPU ASAP (or a Classic user to upgrade to be honest) as most 'regular' users will just check out Amiga demos on YouTube if that scene interests them!

If I have the real HW, I dont want to have to watch demos made for it on YouTube.
Whats the point?

Heck, I only got a BPPC+BVision so I could watch a handful of demos made for this combo on the actual HW :hammer:

For me, its the real thing or nothing, regardless of platform.
Title: Re: When is an FPU chip really needed????
Post by: guest11527 on June 19, 2017, 10:11:59 PM
Quote from: Oldsmobile_Mike;827346
C64 ran at 1.0MHz.  Actually I think it was 1.02MHz, or something like that (6510 vs 6502), but now we're just splitting hairs.  :lol:

Who's talking about the breadbox? I'm *of course* talking about the predicessor of the Amiga, the Atari 8-bit machines by Jay Miner. (-:
Title: Re: When is an FPU chip really needed????
Post by: Iggy on June 19, 2017, 10:45:38 PM
Quote from: Thomas Richter;827349
Who's talking about the breadbox? I'm *of course* talking about the predicessor of the Amiga, the Atari 8-bit machines by Jay Miner. (-:


I'm a big fan of hacking 8 bit Ataris (I even have one 130XE with a 63B09 in it).
But the gpu steals cycle from the cpu in that design, making the difference between a 1 MHz "breadbox" and a 1.78 MHz Atari negligible.
Beside, those two rely on MOS cpus, and I've always preferred real Motorola. :)

It is curious that the 68000 doesn't access memory any faster (just over a larger bus), what the 8 bit cpus do in one cycle, the "better" cpu takes four cycles to accomplish.

I kind of miss the 8 bit stuff (except for that 64K address limitation).
Title: Re: When is an FPU chip really needed????
Post by: kolla on June 20, 2017, 12:05:22 AM
Quote from: Thomas Richter;827340
Ok, so let's see. This search results in 178 packages of a total 81912 packages

Should we make a point of distinguishing between what contains running binaries and what is merely content? And then make a point of distinguishing between what can be considered useful software and what is rather redundant? And then make speed/accuracy comparisons on what is left?
Title: Re: When is an FPU chip really needed????
Post by: kolla on June 20, 2017, 12:13:28 AM
Quote from: BozzerBigD;827344
@UberFreak

That's not a compelling argument for the Vampire getting a FPU ASAP (or a Classic user to upgrade to be honest) as most 'regular' users will just check out Amiga demos on YouTube if that scene interests them!


Most regular users will also check out games on YouTube, and using UAE.
Title: Re: When is an FPU chip really needed????
Post by: kolla on June 20, 2017, 12:18:45 AM
Vampire is nice for watching demos from YouTube after having them tediously converted and downscaled to suitable mpeg1 using ffmpeg or whatever (preferably on much faster system).
Title: Re: When is an FPU chip really needed????
Post by: UberFreak on June 20, 2017, 01:25:44 AM
Quote from: kolla;827358
Vampire is nice for watching demos from YouTube after having them tediously converted and downscaled to suitable mpeg1 using ffmpeg or whatever (preferably on much faster system).

Low blow, but you win :)
Title: Re: When is an FPU chip really needed????
Post by: guest11527 on June 20, 2017, 07:00:56 AM
Quote from: kolla;827353
Should we make a point of distinguishing between what contains running binaries and what is merely content? And then make a point of distinguishing between what can be considered useful software and what is rather redundant? And then make speed/accuracy comparisons on what is left?

There are lies, damn lies, and statistics. May I remind you that you started counting packages as argument?  Frankly, I can only tell you from my personal use case that only a minority of programs profits from the FPU, and an even smaller amount really requires it. I cannot tell you if that's 0.2%, 1% or 5%, but it's all in the same order of magnitude, namely "negligible".
Title: Re: When is an FPU chip really needed????
Post by: kolla on June 20, 2017, 12:45:17 PM
Quote from: Thomas Richter;827360
There are lies, damn lies, and statistics. May I remind you that you started counting packages as argument?


It was not an argument, it was an attempt to answer the question asked - "when is an FPU really needed" - the answer is not "never".

Quote
Frankly, I can only tell you from my personal use case that only a minority of programs profits from the FPU, and an even smaller amount really requires it. I cannot tell you if that's 0.2%, 1% or 5%, but it's all in the same order of magnitude, namely "negligible".


It all depends on what software you install and use, and how you use them - the number of binaries is rather irrelevant, what is relevant is _what_ binaries, and whether the user sees a need to use those.

For example - do you want to use TV-paint? Then you need FPU.

Is TV-paint negligible? Maybe, for "most users". But so what.
Title: Re: When is an FPU chip really needed????
Post by: OlafS3 on June 20, 2017, 04:27:38 PM
Quote from: Thomas Richter;827360
There are lies, damn lies, and statistics. May I remind you that you started counting packages as argument?  Frankly, I can only tell you from my personal use case that only a minority of programs profits from the FPU, and an even smaller amount really requires it. I cannot tell you if that's 0.2%, 1% or 5%, but it's all in the same order of magnitude, namely "negligible".

Give up with Kolla

FPU and MMU are religions

Gunnar is evil promising them (how he thinks) and now not fulfilling those promises having him bought useless piece of hardware (again his view). I asked him why he not sells the two boards he claims to have bought, then there would be two new happy user and one unhappy less and no need anymore to moan about Gunnar but it seems he not wants that. He and Matthey (both for different reasons) are on a kind of crusade against gunnar and his project. It is really a strange community...
Title: Re: When is an FPU chip really needed????
Post by: OlafS3 on June 20, 2017, 04:29:33 PM
Quote from: UberFreak;827359
Low blow, but you win :)

yes but he always claims that he has bought two vampire boards

why did he that? To convert down videos to watch those?

why did he not stay with UAE?

Lots of questions and no answers...
Title: Re: When is an FPU chip really needed????
Post by: guest11527 on June 20, 2017, 04:46:54 PM
Quote from: Iggy;827351
I'm a big fan of hacking 8 bit Ataris (I even have one 130XE with a 63B09 in it).
But the gpu steals cycle from the cpu in that design, making the difference between a 1 MHz "breadbox" and a 1.78 MHz Atari negligible.
That's likely true. The Atari 8-bit are an older design, and it shows in some cases. Yet, it is a fascinating design whose second edition became the Amiga.


Quote from: Iggy;827351
It is curious that the 68000 doesn't access memory any faster (just over a larger bus), what the 8 bit cpus do in one cycle, the "better" cpu takes four cycles to accomplish.
The 68000 is a fully microcoded CPU, i.e. every instruction is executed by the microcode engine and hence takes several micro-code instructions to complete.
The 6502, however, is completely hardwired silicon, and hence does more work per cycle. With the known defects the simple 6502 design caused, namely instructions with unknown side effects, unimplemented instructions and instructions that hang the CPU completely. Motorola changed this for the later members of the family, i.e. many instructions in the 68060 are also hardwired (with some errata in the early masks due to the complexity of the design).


Quote from: Iggy;827351
I kind of miss the 8 bit stuff (except for that 64K address limitation).
You can still program and run programs on the 8-bits, of course. I'm working with the ca65 assembler and the Atari++ emulator. Works quite nicely.
Title: Re: When is an FPU chip really needed????
Post by: David Wright on June 20, 2017, 05:15:07 PM
Kolla my friend, you have to stop this crusade. We will get what we get, that's it.
Sell yours and come back to it later or enjoy for what it is.

I was disappointed about TV paint also. Lot's of others work well like Photogenics.
I'm still thinking at some point there will be more compatibility.

Look, we get a nice product that we enthusiastically buy and enjoy. Every so often an update comes and probably gives you a feature that makes it that much more enjoyable.

Sometimes, as in life, it's the journey not the destination.
Title: Re: When is an FPU chip really needed????
Post by: Iggy on June 20, 2017, 07:39:05 PM
Quote from: Thomas Richter;827376
That's likely true. The Atari 8-bit are an older design, and it shows in some cases. Yet, it is a fascinating design whose second edition became the Amiga.
...

Absolutely, both Jay Miner at work.
And I like what the Atari community has managed to do with the 8 bit machine (which frankly appeals to me more than the STs).

Lotharek's boards are particularly interesting (especially the fpga gpu board). And like I said, I have one 130XE with a Hatachi 6809 derived cpu in it.
In some ways, like you mentioned, kind of a "Proto-Amiga".