How can one add more memory than 128MB to a A4000 Cyberstorm PPC

[Painkiller]

Uhh I must be really tired... First I read that you said you can get silly me.

So there is actually no way for me to take use of these babies in any way with A4000

[Vlabguy1]

So that being said what is the max amount of ram a big box Amiga can hold?  with memory slot expansion and Zorro board memory cards..even with several
Fastlanes..etc.
Just curious

Rich
ny

alexh wrote:
You cannot. 128Mbytes is the maximum the CSPPC can take.

If you need more RAM the only option is to buy a Zorro board with memory such as a DKB3128, Fastlane etc.

[McVenco]

Vlabguy1 wrote:

So that being said what is the max amount of ram a big box Amiga can hold?  with memory slot expansion and Zorro board memory cards..even with several Fastlanes..etc.

I've got a CSMK3 with 128MB and a DKB3128 with 128MB, so 256 in total, but I've heard somewhere that some guy tried three DKB boards, so that's at least 500+MB.

IIRC the total RAM address space (or whatever it's called) on an A4000 is 2GB (could be 4GB, I'm not sure), but you just don't have enough Zorro slots to fill them up to 2GB.

[Amigaz]

Be warned, OS4 doesn't boot completely if you have a Z3 Fastlane in your machine "been there, done that"  :-)

[jj]

Are they not converters for simm to edo

or did I dream that ?

[mongo]

alexh wrote:
There is no DMA on most PCI bus boards between the host CPU and PCI and so if there were any RAM cards they (AFAIK) would not be supported.

There is no DMA between the host CPU and anything.

In theory, you could use the frame buffer RAM of a PCI video card as system memory, as long as you weren't using it for video too. You'd have to write code to initialize the RAM controller on the card and AddMem the RAM to let the system know it was there.

Not really practical, but it could be done.

[Zac67]

Yeah, used my Merlin Z3 card like that - to increase the sampling buffer for a Maestro.

For OS4 you can only use accelerator RAM, no Z2, no Z3 or whatever card RAM.

[alexh]

mongo wrote:

alexh wrote:
There is no DMA on most PCI bus boards between the host CPU and PCI

There is no DMA between the host CPU and anything.

You are of course right. I am thinking about a different issue which is that non of the PCI bridge boards are Zorro III DMA masters, which has nothing to do with RAM.

[Vlabguy1]

Cool..your system must be pretty zippy then..as well as being able to have many programs running.

Rich
ny
mmm..can someone make a PCI memory card..

McVenco wrote:


I've got a CSMK3 with 128MB and a DKB3128 with 128MB, so 256 in total, but I've heard somewhere that some guy tried three DKB boards, so that's at least 500+MB.

IIRC the total RAM address space (or whatever it's called) on an A4000 is 2GB (could be 4GB, I'm not sure), but you just don't have enough Zorro slots to fill them up to 2GB.

[alexh]

Vlabguy1 wrote:
mmm..can someone make a PCI memory card..

$2k and it's yours.

[darksun9210]

erm, right, wow this thread fills up fast!
a3/4k machines are limited to 128MB for the cpu slot.
i'm not sure if there is a zorro3 limit of 1.76GB or 2GB or if its the full fat 4GB (minus system board devices) i could look it up, but its friday and i'm actively being lazy.

the A1200 is able to take more than 128Mb as it doesn't have to map out xGB for zorro3 space, so all the 4Gb memory space above the standard amiga devices area is free for use. hence you can have 256Mb ram on a blizzard030.

same for the A500/600/CD32 when fitted with relevent accelerators - but these only had one simm slot so only 128Mb is possible.

not sure about the A2000. as that doesn't have to worry about zorro3 space. but then you just have to get over the possible issue that the memory controller logic on the accelerator might not understand more than 128Mb.

so some 060 based A2000 accelerator with standard 72pin simm slots would be your best bet.

in theory, each zorro3 slot can take up to 512Mb address space (possible ram). i've been thinking on brewing a zorro3-to-DDR1 dimm card. obviously it'll be no faster than whatever Zorro3 can drive it at, but its the capacity that would be nice. however, someone has already experimented with 3 DKB128 cards, and a fully loaded accelerator giving 512Mb ram. but it seems there was a bug found in exec which limits addressable _system memory_ to 384Mb. not saying that you can't have anything else in there too eating up address space, just seems the system can't understand more actual RAM than that.

--edit--

you may find that designers/manfacturers may have saved money/time/PCB complexity by only running 25/26/27 address lines to the memory controller making the max addressable ram for that board 32/64/128Mb ram. hence why apollo's for 1200's may max out at 32/64Mb.

[zipper]

darksun9210 wrote:
erm, right, wow this thread fills up fast!
a3/4k machines are limited to 128MB for the cpu slot.
i'm not sure if there is a zorro3 limit of 1.76GB or 2GB or if its the full fat 4GB (minus system board devices) i could look it up, but its friday and i'm actively being lazy.

I think that 1.7 figure is about correct - but may be quite difficult to test...

[darksun9210]

i was going by the mediator addressing 1.76Gb of PCI space through a 512MB window. i guess it is the upper 1.76Gb of the 4GB area, so then you have the 1.76Gb of zorro3 space below that, and the bottom 512Mb left for amiga CPU slot and system devices. Meh. rough guess.

friday! happy happy joy joy