A3000 questions.

Thanks to John I have nice A3000 desktop setup. I have not test it yet as PSU is 110V and faulty :). I have just finished fitting ATX PSU into A3000 psu case - not much space there ...

As I have not experience at all with A3000 I have some questions:

1. CPU on board is 16MHz, can I overclock it to 25MHz, looks like an easy job to do ...? Do I need faster memory for this (mine is 80ns)?

2. SuperBuster turned out to be -07, do you think I have to replace it with -09 at least? I want to fit basic Zorro graphics card (I have CGX64/3d but maybe I will swap it for picasso II - I do not need card like this in my A3000)

3. Ramsey is 04 - need replacing ?

4 . Are there any mods I should do before I close it (mau=ybe SCSI improvements etc.)?

5. How to change it to PAL ?

Board is Rev.9

Will be grateful for any tips.

Regards

Chris

1. I wouldn't bother - leave it at 16MHz and, when appropriate, add a CPU card :D

2. As long as you're only running one card, you should be fine. I seem to remember the issues with previous busters are around running multiple cards that want to bus master. As long as you don't add a deneb, you should be fine. But I am really not sure here :D

3. No, not really. Finding newer ramseys is difficult!

4. Check the LED board - many traces have simply died on these so you might need to repair. REMOVE THE BATTERY!

5. 1 Jumper :D - J200.

If you're running an AT or ATX PSU, change tick clock source (J350)

Enjoy!

Quote:

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Originally Posted by chiark

1. I wouldn't bother - leave it at 16MHz and, when appropriate, add a CPU card :D

2. As long as you're only running one card, you should be fine. I seem to remember the issues with previous busters are around running multiple cards that want to bus master. As long as you don't add a deneb, you should be fine. But I am really not sure here :D

3. No, not really. Finding newer ramseys is difficult!

4. Check the LED board - many traces have simply died on these so you might need to repair. REMOVE THE BATTERY!

5. 1 Jumper :D - J200.

If you're running an AT or ATX PSU, change tick clock source (J350)

Enjoy!

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Thanks m8 :), noted :thumbsup:

I want this A3000 to keep as simple as possible without CPU card so 25MHz would come handy :) .

@bebek

1. Will the 030 make it at 25 MHz? Also, the 68881 will also have to follow at 25 MHz. Will it? Just leave it as it is :)

2. I recall Dave Haynie said Buster -07 does not support bus master DMA at all. So do as per chiark's suggestion.

3. Again as chiark said. Look here.

4. The infamous INT2 mod, also replace the WD -04 SCSI chip for a -08 part or the AMD equivalent.

5. J200 will do, although colour encoding may stay unchanged. I don't really know though. Even so, (most?) PAL monitors can handle NTSC colour decoding AFAIK. You could also swap the 28.6363 MHz crystal (NTSC) for a 28.37516 MHz one (PAL).

If you do change the speed, I think you may need to change rom access timing jumpers too, but I really can't remember... Good luck!

I love the 3000: it's built like a tank. Somehow it's the OCS/ECS machines that really best reflect the Amiga age for me: perhaps it's because I didn't buy a 4000 until 1995!

Quote:

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Originally Posted by chiark

Somehow it's the OCS/ECS machines that really best reflect the Amiga age for me

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+1 :thumbsup:

You don't need faster memory to overclock to 25 MHz. You just change the Ramsey speed jumper (J851) to 25 MHz. But it really depends on your long term plans for the A3000 and whether your satisfied with the performance of a 25 MHz 030.

Super Buster rev. 7 does not support Zorro3 DMA but should work fine with any non-DMA Zorro3 card.

There is probably no real need to upgrade Ramsey unless you upgrade SuperDMAC as well. But SuperDMAC rev. 4 is a very rare and expensive chip to replace.

The main reason why A3000's, A2000's and A500's seem more durable than an A4000 or A1200 is probably because they have more reliable thru-hole caps. Although, all Amiga's can suffer from Ni-Cad battery leakage problems.

^^^^ This man knows what he's talking about. I don't :D

What I was meaning with the reference to ROM speed was the ROM timing jumpers, J150 and 151. From a quick google

Code:

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J150, J151:    ROM Timing.
The ROM timing circuit provides four different speed settings to
match the output enable and access timing of the system ROMs.
To set the jumpers, determine the output enable time and access
times for the ROMs you wish to use. 
The ROM must have lower valuesthan for the setting you select.
 System standard ROMs have T(oe) = 110ns and T(acc) = 250ns.
 CLK    J151    J150    T(oe)(min.) T(acc)(min.)
 16 MHz  2-3    2-3    157ns      250ns
 16 MHz  2-3    1-2    220ns      312ns
 16 MHz  1-2    2-3    282ns      375ns
 16 MHz  1-2    1-2    345ns      437ns
 25 MHz  2-3    2-3    90ns        160ns
 25 MHz  2-3    1-2    130ns      200ns
 25 MHz  1-2    2-3    170ns      240ns
 25 MHz  1-2    1-2    210ns      280ns

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..and DENEB don't like mixed ZIP RAM memory & old Buster 07 (also 09 ?)

Thanks guys for tips.

so far:

I have done INT2 mod - just in case while board was out :),
fitted socket for CPU crystal - starts fine with 25MHz but have no system yet to test it
battery is out
new PSU works perfect

There is no Deneb for this beauty :) only tandem IDE ... and Yamaha SCSI to IDE. One SCSI device so WD -04 should be ok ...