Introducing ACA 1221 Low Cost Accelerator At AmigaKit.com

[dirkies]

I had to send mine back. Requires some hardware to flash i believe.

[Schoenfeld]

Originally Posted by Xebec

Hi Jens! - I assume there is no way to 'flash' an ACA1221 from Rev 1.2 to Rev 1.3? It's some kind of hardware difference? I wanted to try 42 mhz ever since I saw how you divided out the mhz to get 17, 21, 28.. Thanks

It's a combined CPLD and flash update. Both require special tools that the average user does not have, and I would not part with the required files :-)

You have probably read in the Wiki that not all 68020 CPUs can take that kind of overclocking. Also, it appears like the power supply has great influence on overclocking capabilities: Just 0.1V too much, and the CPU gets too hot to run at 42MHz, although the mask is right. Cooling is a "must", but it's very difficult with the CPU upside down and no mounting holes on the card.

Jens

[Xebec]

Originally Posted by Schoenfeld

It's a combined CPLD and flash update. Both require special tools that the average user does not have, and I would not part with the required files :-)

You have probably read in the Wiki that not all 68020 CPUs can take that kind of overclocking. Also, it appears like the power supply has great influence on overclocking capabilities: Just 0.1V too much, and the CPU gets too hot to run at 42MHz, although the mask is right. Cooling is a "must", but it's very difficult with the CPU upside down and no mounting holes on the card.

Jens

Fair enough - I appreciate the response

My first OC was a 486DX-25 that eventually ran at 48 mhz in 1992 (wouldn't do 50).. It's just a ton of fun to OC these old processors to me.. wanted to at least give it a try but understand..

Thanks for this great accelerator btw!

[Zippy Zapp]

Hi. Is there any update on the new model ACA1221 or the ACA500plus?
Thanks. Revisions look good.

[Marchie]

Looks good, but no FPU?

[demolition]

Originally Posted by Marchie

Looks good, but no FPU?

What would you need an FPU for?

[Zetr0]

@demolition

Come come now Doctor Zoidberg, you know at least some of these reasons =)

1. Productivity : Ray-Tracing, Image & Video Decompression routines, 3D Modeling
2. Games : 3D Bit-mapped, 3D Polygon
3. Visual Aesthetics : Completeness

[demolition]

Well, for (1) and (2) I wouldn't consider a 68020 based accelerator anyway. My point was that if you need an FPU, you'd probably want an 040 or faster. For (3), it is hard to argue against, although if you want completeness then an 020 will not leave you satisfied for very long.

[Schoenfeld]

For "completeness", a 68020 also needs the 68851 MMU. Then again, the ACA1221 and the forthcoming ACA1221EC are geared towards people who want slightly more memory and a bit more CPU oompf to run WHDload games.

Jens

[geir]

Originally Posted by Zippy Zapp

Hi. Is there any update on the new model ACA1221 or the ACA500plus?

I'm wondering too. Is there a spec list for the upcoming ACA500plus? And will it be released this year? Sorry if this has been asked a million times before. I've been out of the loop for a long time.

[Zetr0]

Originally Posted by Schoenfeld

For "completeness", a 68020 also needs the 68851 MMU.

This explains my attraction to the A2620

Originally Posted by Schoenfeld

Then again, the ACA1221 and the forthcoming ACA1221EC are geared towards people who want slightly more memory and a bit more CPU oompf to run WHDload games.

Jens

Indeed, its horses for courses - very few games use an FPU and I cannot think of any that use an MMU - why spend money one something one wont need or use.

[kolla]

Offloading math intensive software to an FPU makes a world of difference with the software that is able to use it. A 68020/030+882 is still a heck lot cheaper than a 060, and 040s tend to go warm. I really don't grasp this "hostility" against FPUs, especially when they are as cheap as they are.

[demolition]

Originally Posted by kolla

Offloading math intensive software to an FPU makes a world of difference with the software that is able to use it. A 68020/030+882 is still a heck lot cheaper than a 060, and 040s tend to go warm. I really don't grasp this "hostility" against FPUs, especially when they are as cheap as they are.

People who buy cheap accelerators usually want them for WHDLoad stuff. There is no need for an FPU for that and thus it just adds cost. If you really want to run high end stuff that requires an FPU, you'd probably want something faster than an 020/030. This is why I think low end accelerators with FPU are not particularly useful, at least for the general Amiga user.

[dJOS]

Originally Posted by demolition

People who buy cheap accelerators usually want them for WHDLoad stuff. There is no need for an FPU for that and thus it just adds cost. If you really want to run high end stuff that requires an FPU, you'd probably want something faster than an 020/030. This is why I think low end accelerators with FPU are not particularly useful, at least for the general Amiga user.

I chucked a 68882 in my LCIII 030 Mac cause it was cheap and it made a noticeable difference.

Now I realise classic Mac's do almost everything in software and the Amiga uses custom chips, but I'd still have thought for anything using floating point math there would be a significant speed up?

[idrougge]

Which is Demolition's point. There's nothing in WHDLoad or its slaves that uses FPU.

[demolition]

Originally Posted by dJOS

I'd still have thought for anything using floating point math there would be a significant speed up?

Actually, most software that can use the FPU will not even run if you do not have one (you get a guru if you try to execute FPU instructions without one present), so it is not just a question of speed. Some software was compiled in a FPU and non-FPU versions, and here it usually makes a difference if you can run the FPU version, but you won't see that with much classic software. Software that could benefit from an FPU was usually 3D software and games, which was mainly designed for high end Amigas, i.e. 040/060.

[turrican9]

FPU is also needed if you want to use midi music for PC games in scummVM I think. But what's the point having Amiga to emulate PC games? lol

I want Amiga to run Amiga software. If I want to play old PC games I do it on a PC. But hey, that's just my opinion

[dJOS]

Originally Posted by turrican9

FPU is also needed if you want to use midi music for PC games in scummVM I think. But what's the point having Amiga to emulate PC games? lol

I want Amiga to run Amiga software. If I want to play old PC games I do it on a PC. But hey, that's just my opinion

Lol, yeah that is what DosBox is for.

[dJOS]

Originally Posted by demolition

Actually, most software that can use the FPU will not even run if you do not have one (you get a guru if you try to execute FPU instructions without one present), so it is not just a question of speed. Some software was compiled in a FPU and non-FPU versions, and here it usually makes a difference if you can run the FPU version, but you won't see that with much classic software. Software that could benefit from an FPU was usually 3D software and games, which was mainly designed for high end Amigas, i.e. 040/060.

What about the various paint programs, surely they support FPU's?

[whiteb]

Originally Posted by dJOS

What about the various paint programs, surely they support FPU's?

Not usually.

Paint programs usually do not require floating point arithmetic.