Natami style SuperAGA card for A4000/A1200?

[slaapliedje]

Maybe this has already been talked about, maybe not.  Just too damned tired after having a rather strange day at work to bother looking.

But I've been thinking about this for a while now.  My biggest complaint right now about my A4000D is the AGA chipset.  It seems to just fly when in 64 or less color mode, but in 256 color mode, work bench crawls, has weird redraws, etc.

I am simply dying for the Natami to come out, but the question always comes up "well when / if it ever comes out, what will be the damage to my wallet?"  I'm also wondering if it'd be easier to create a new, faster, better AGA upgrade somehow to allow for faster 256 (or more) work bench?

I'm sure there have been discussions on this in the past.  There is the "why don't you just get a Mediator and Radeon or Voodoo card" or "find some Picasso Card on eBay."  Well mainly due to compatibility and well.. the screen dragging and independent resolutions is why, damnit!  I know the real reason it's slow is due to the really old AGA chipset, because Workbench seems to just fly under my Radeon (yes I do have a Mediator board with a Radeon, though I have weird random lockups with it).

Besides a faster video chip, an accelerator that didn't make me feel like I was mugged would be nice as well.  I'm still running a stock 040.  The thing is, Workbench has certain things that actually feel snappier than my 8core AMD (in either Windows 7 or Linux).  Not sure what it is, but it's just awesome.  

Anyhow, one can dream, right?

slaapliedje

[XDelusion]

That's what I'm saying...

Well sorta...

We need some sort of video card for 1200's and 600's. The current limitations have suited us well over the years, but at this point, a little upgrade would be grand! And I'm not talking mere flicker fixers either (though those are nice to have too).

[commodorejohn]

I'm not ultra-familiar with the internals, but I doubt there's a way to un-map the existing chipset from its position in memory, and while you could solve that by making it part of an accelerator, I'm not sure that you could get DMA to/from the replacement chip RAM to work with expansion cards that way. It seems like it'd be more trouble than just getting a Natami, and likely no cheaper.

[freqmax]

If you can have someone make an Zorro-III card with an (Xilinx) FPGA with an suitable video output, an RTG replacement should be doable.

Now if one put the CPU, and RAM onto the same card there's less inner workings to deal with. But then it's essentially a new computer. So you could essentially just buy an FPGA Replay.
I think it all depends on how much of the original hardware you want to keep using, chassi, keyboard, mouse, Zorro-slots, CPU, etc..

[bbond007]

But I've been thinking about this for a while now.  My biggest complaint right now about my A4000D is the AGA chipset.  It seems to just fly when in 64 or less color mode, but in 256 color mode, work bench crawls, has weird redraws, etc.

I am simply dying for the Natami to come out, but the question always comes up "well when / if it ever comes out, what will be the damage to my wallet?"  I'm also wondering if it'd be easier to create a new, faster, better AGA upgrade somehow to allow for faster 256 (or more) work bench?

The FPGAARCADE is your only hope now that the Natami fire has fizzled out... but that is only going to support a GFX card mode, and not a superset of AGA.

Anyway, I agree that AGA was a little slow out of the gate - about 1/2 the speed of a mac of that era in 640x480 (multiscan) 8bpp mode. They were also less than 1/2 the price. Commodore probably expected most people to use a NTSC monitor like a 1084 anyway...

If you have an Indivision AGA MK2 you may see a driver in the future that does not slow down so much running in higher resolutions or depth. The driver would accomplish this by turning off screen DMA while writing to the video buffer. Normally this would cause the screen to blank out but the Indivision would frieze the image until DMA is reenabled. You could see a quicker ShapeShifter or WorkBench driver.

In higher resolutions and color depth the machine just spends way too much time being locked out of the chipram just displaying the screen. 256 color mode in theory should be 1/2 the speed of 16 color mode, but as you know, its much slower than that. Not only do you have twice as much memory to move, but you have to use a much smaller shovel.

Also screen changes would probably appear instantaneously and you would never actually see anything being drawn. That last part is just speculation on my part though.

[Hattig]

One thing the FPGAArcade has going for it is far faster memory, so even if the AGA implementation has no enhancements, the 256 colour modes should perform a lot faster simply because there will be far less contention on the memory bus.

Wonder if you can put faster chip RAM in an A4000 to help the performance in AGA?

[slaapliedje]

One thing the FPGAArcade has going for it is far faster memory, so even if the AGA implementation has no enhancements, the 256 colour modes should perform a lot faster simply because there will be far less contention on the memory bus.

Wonder if you can put faster chip RAM in an A4000 to help the performance in AGA?

Now that's an idea!  Though I don't know how you'd really do that, I think the fastest SIMMs they made were 60ns, right?  Are the default ones 72ns?

If you have an Indivision AGA MK2 you may see a driver in the future  that does not slow down so much running in higher resolutions or depth.  The driver would accomplish this by turning off screen DMA while writing  to the video buffer. Normally this would cause the screen to blank out  but the Indivision would frieze the image until DMA is reenabled. You  could see a quicker ShapeShifter or WorkBench driver.

There's an idea, except that I have the original Indivision AGA.  Actually I kind of like that I got that anyhow, since I have the VGA of it, the DVI of the Radeon and HDMI from my main PC all connected to my 24" LCD.    But if it's just a driver update, the question is will it work with the Indivision that I have?

slaapliedje

[matthey]

One thing the FPGAArcade has going for it is far faster memory, so even if the AGA implementation has no enhancements, the 256 colour modes should perform a lot faster simply because there will be far less contention on the memory bus.

The blitter should be significantly faster (unless they slow it down for compatibility) and would work with the faster gfx memory to give even a bigger speedup. The RTG chunky modes will reduce the amount of work needed also providing a speedup.

Wonder if you can put faster chip RAM in an A4000 to help the performance in AGA?

I believe the Boxer was going to have faster chip ram. C= was brain dead for not constantly upgrading the speed of the custom chips and chip memory. The custom chips were an accelerator on the 68000 but a bottleneck for some operation on an Amiga that had a 68020+. AGA did upgrade the speed over OCS/ECS but not enough for how late it came.

[Akiko]

But I've been thinking about this for a while now.  My biggest complaint right now about my A4000D is the AGA chipset.  It seems to just fly when in 64 or less color mode, but in 256 color mode, work bench crawls, has weird redraws, etc.
slaapliedje

A Natami style graphics card is highly unlikely, best available option for the 4000 is a Mediator busboard with Voodoo 3 / Radeon 9250 card.

[utri007]

Every ole who have 040 or better should installa and configure FBlit.
It makes big difference.

[Forcie]

The FPGAARCADE is your only hope now that the Natami fire has fizzled out... but that is only going to support a GFX card mode, and not a superset of AGA.

The Natami is still in development, just without any major public announcements lately. The mainboard is currenctly getting a redesign. I run a beta system at home with an earlier board revision.

I agree that the FPGA Arcade seems like a well designed system though. I will probably get one when the expansion board is available too.

Regarding the original question, a SAGA card for Amiga would require piggybacking just about every custom chip and would probably be super unstable due to all the connections You are better off picking some RTG solution.

[AAACHIPSET]

i always  hoped  that any upgrade board  or if another amiga was  built ..unlikley..that
we may have seen  a version of the AAA chipset ..if  natami  was the superaga  how  much better or worse  would it have been than AAA..since my understanding was that
the AAA chipset  was  more than just a graphics  upgrade ??

[freqmax]

I suspect at the point that you succeded with an upgrade to A4000 to give it hotter graphics. It's not much left of the original electronics except the keyboard and power supply

So work the other way, make an Zorro-III expansion board for the FPGA Arcade. Then you will have any graphics (and CPU) that can be coded for.

Faster chip-ram might be an idea, but it also requires that the graphics and CPU chips makes use of it. One approach could be to use RAM fast enough to complete an access cycle fast enough to simulate dual-port RAM for CPU and graphics simultainously.

As for AAA:
https://en.wikipedia.org/wiki/Amiga_Advanced_Architecture_chipset

[dreamcast270mhz]

Perhaps someone could make a DIMM to SIMM interface. This interface could have 16Mb of significantly faster than 60nsecs RAM onboard, or even more with bankswitching. Of course, I have no idea how to engineer it...

[commodorejohn]

But by the time you get up to SIMMs/DIMMs it all has to go through the onboard memory controller, doesn't it? That's the reason I haven't put faster RAM in my 386, even though 12MHz RAM on a 40MHz system is an obvious bottleneck: the memory controller can't keep up with anything faster.

Really, that's the problem with the whole idea: there's a lot of hardware in the Amiga that's designed to be superceded by things like RTG, but not replaced with a functionally-equivalent enhancement. In order to replace all of it, you'd likely have to replace so much of the system board that it'd be easier just to build a full system replacement...