Fast memory limit on A2000. 8Mb?

[Clueless]

I've read somewhere that the A2000 limits fast ram to only 8Mb.

My A2000 has an A2630 (030 accel with 68882 fpu and 4Mb 32bit ram onboard)  but this Amiga also has a Microbotics 8-Up card fully populated (8mb).

Even though the system really has 12mb fast plus 1mb chip, WB3.1 reports only 8Mb of fast ram and 1mb chip.

Can I use all this memory with my A2000 or am I stuck with 8mb?  Any hints on configuring it?

Thanks!

[that_punk_guy]

AFAIK you should be able to have fastmem above that limit located locally to the accelerator with an '030 card. It should autoconfigure at boot-time.

I dimly recall problems with A2000s not reporting the right amount of fastmem but I dunno what the upshot of that is... although I've definitely heard of people using A2000s with more memory than you have.

Someone else will hopefully have more answers for you! :-D

[QuikSanz]

Hi,
Try removing the microbotics card and see if your sys
shows 4Mb ram. What OS? As I think about it I seem to
remember when you plug in a Accel card it remaps the
memory. Don't remember exactly, but thats the direction
I'd be looking.

Chris

[Crusher]

In my A2000, I had a CSA Derringer with 32MB and a GVP scsi with 8MB and got 40MB out of it plus the chipmem, pretty fast and a good Lightwave machine it was. Regret that I sold it.

Ok, this didn´t answer your question but maybe it gave alittle info.  :-)

Hi Clueless,

You can go beyond the Amiga 2000 computer's 8 Meg limit by first removing the Microbotics 8-Up card and installing either a DKB 2632 or an Access 32 onto the memory expansion plug on the back of the A2630 board.  The DKB 2632 uses SIMMs and will take up to 112 MBs.  The Access 32 uses ZIPs and takes up to 32 MBs.  In the mean time, if you want your Amiga 2000 to be more stable, remove 4 megs of memory from the Microbotics 8-Up board, so that there is only 8 megs of fast ram in your system.  Make sure that the 4 megs of 32-bit memory on the A2630 board is the FIRST fast memory that the Amiga 2000 sees, then the Microbotics 8-Up boards 4 mags of memory.     :-)

[jeffimix]

The Zorro 2 slots can only address 8 megs of memory. This is the worst place for lots of memory, because the full 8 megs will interfere with other equipment on the Zorro2 slots ( like say a GFX card with memory onnit) With an accelerator card, I've heard of 128 Megs, and maybe with the Blizzard 2060, more would be possible.

[Clueless]

So am I understanding right that I can have the full 8mb on the 8-Up! zorroII card and it should not interfere with the 4mb of 32bit ram (zip packages) in the A2630 accelerator?

I tried temporarily removing the 8-Up!  card, just leaving the A2630 with its 4mb in.  WB3.1 then reports the 4mb of fast ram.

I reinsert the 8-Up! card and then WB3.1 reports only 8mb of fast ram (not the expected 12mb).  :-?

[cha05e90]

Hi!

8 MB is ok. The Microbotics-ZorroII-RAM AND the 2630-onboard-RAM are BOTH inside the ZorroII-limit. You cannot go further than 8MB (within this ZII-limit), so 4MB are "löst" and of no use. It is a HARDWARE limit, so changing the OS will not help. The only way to get more RAM into your A2000 is a newer accelerater board (A2040/2060) that allocates its memory OUTSIDE the ZII region or as "anonymous" said,  to put a RAM-addon-board to your A2630 (i.e. dkb 2632).

Regards,

Frank.

[Crusher]

So you mean that if I have a CV64/3D I have to take out 4MB from my GVP-scsi that has 8MB on it?  :-?

[Kronos]

@Clueless

There a sane accels, and there are accels made by C= ....

The 2630(and 2620 too) do put there RAM into the 8MB-Zorro2-FAST-MEM-area,
leaving only 4MB (or 6 if you only have 2 on the accel), for other expansion.

C= PC-Bridgeboard take another 2MB, and GFX-Card 2 or 4 (except the Picasso2 in
slow-mode ....). But you don't have any of this.

Back to the point, C= accels are rather robust, but they are a nightmare for anybody
wanting to get the max out of his system.

[Colmiga]

>So you mean that if I have a CV64/3D I have to take out 4MB from my GVP-scsi that has 8MB on it?

Not in the case of a 3000T which has Zorro III capability. Because the CV3D is an ZII/III autosensing card it will map its mem into the ZIII address space on your system.

It is only people who use Zorro II only cards or Amiga systems that need to worry about the 8MB mem limit.

[vortexau]

Exactly! Physical RAM on ZorroII cards maps into the 8MB limit (16Bit Address) space. Standard Zorro II cards (on a Zorro II Bus) all added togather can't exceed 8MB.

The CPU Card fitted into the CPU Slot is within 32Bit Address Space with a much higher limit!

GVP Acellerators handle their RAM differently . . . . . allowing the RAM (on THEIR acellerators) to be configged as inside the 8MB space, or in the expanded RAM (32Bit Address) space.

I owned a GVP 030 board in the mid nineties with 4MB on board. In the same period, I obtained an extra 4MB of GVP RAM & a Picasso II graphics card with 2MB of Gfx RAM.

To get the Picasso II to work; I configged 4MB on the GVP 030 to stay within the 8MB space, and the other 4MB to be mapped as expanded RAM.
 . . . . . . .
Presently I have a Blizzard 2060 acell-board with 64MB, which would be ALL in expanded RAM; or . . . 32Bit Address Space.

[Crusher]

"Not in the case of a 3000T which has Zorro III... "

;-) That I knew, but we did talk about the A2000.

The computer I have in my sign is only the computer I use most. I also have three A1200, two A2000, two A3000D, one A600, one A500 and my belowed A3000T.
Don´t take this info as brag please, I´m just a nutty Amigalover.  :-)

So back on topic.

[Clueless]

Now I understand. I thought the 4mb on the A2630 were handled differently (outside the ZII).

I now reconfigured (jumpers) the 8-Up! card to use only 4mb.  I check the ram allocation with a gvp info tool and effectively reads 4mb on the accel and 4mb on the 8-Up!

So now my choice of ram expansion beyond 8mb is to somehow get a hold of dkb ram board to plug into the back of the A2630.

This forum is invaluable.  Thanks everyone!  :-)

[Markus_Bieler]

So now my choice of ram expansion beyond 8mb is to somehow get a hold of dkb ram board to plug into the back of the A2630

Make sure that the connectors on the A2630 are on the solder side and not on the componentside. C= made a batch with the connectors on the wromg side.