A3640 in A3000D

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I recently acquired an A3640 (v3.1) card. I followed the instructions below for installation in my Amiga 3000 desktop. The A3K has v3.1 ROMs, DMAC-02, RAMSEY-04 and BUSTER-11.

http://l8r.net/technical/t-a3640.shtml

Unfortunately, the A3000 does not boot with the board inserted. The power LED never changes from dim to bright and does not attempt to access the hard drive. It just gives me a blank screen.

The instructions indicated that the older DMAC/RAMSEY combo may present a problem with SCSI operation and advised to upgrade to the latest chips, but did not mention it causing boot problems.

I also checked my fast slot and all appears well.

Any ideas?

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Yes, checked and double-checked with a nice, bright flashlight.  

dannyp1 wrote:
I've put A3640's in a couple of A3000's but I had the updated Ramsey & DMAC chips.  You double checked all of the jumpers, correct?  I had some trouble once putting a MKII 060 in a 3000T and I had to try several different jumper settings until I found one that worked.

Dan

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No, sorry I did not clarify-- I have the 25MHz '030 version (9.03) motherboard.

amiga_3k wrote:
Is your A3000 a 14 MHz 030 version? I had one of those and had to have it modified to make use of the 3640. Don't ask me what has been modified as I had Vesaila taking care of it.

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The info on that page appears to be the same as the site I posted. The chip located at U209 on my card is -02, by the way.

rkauer wrote:
 Quoting The Big Book of Amiga Hardware:

V3.1

This card works fine in general however it does have a bug related to Zorro II DMA that causes some cards like the GVP Phonepak to stop working, when installed in an A3000. The PAL or GAL chip located at U209 should be -02.

Installation in an A3000

Jumpers

J100: CACHE & MMU at startup
Pins 1-2 Closed: Caches enabled
Pins 3-4 Closed: MMU enabled

J400: MAPROM

1-2 Closed: MAPROM enabled
3-4 Closed: MAPROM disabled

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On a side note- can the updated DMAC and RAMSEY still be had somewhere? I checked Softhut but the prices seemed rather high.

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That's a bummer.

I was told the board was fully functional when I purchased it. It was from a trustworthy source.

I'm very, very positive I'm using 3.1 ROMs since I installed them myself and I'm looking right at the labels that say so...not to mention that I couldn't boot OS 3.9 without them.  

alexh wrote:
They do not have stock anyhow. You'll be hard pressed to find a DMAC 04 anywhere except another A3000 (which sort of defeats the point).

Have you confirmed the A3640 is in working condition?

Are you 100% sure you do not have KS1.4 boot ROM's? Lots of A3000's without accelerators have KS1.4 which can softkick into KS3.1 If you did not buy the KS ROM's it would be worth double checking?

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Yep. I did follow these instructions per the guide....unless you're saying the guide is incorrect.

joekster wrote:
I think you may have to set the clock source jumpers on the motherboard to external.

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That matches the guide and my current settings.

da9000 wrote:
I agree with joekster. Check your motherboard clock jumpers.

If I recall correctly, you want:

J104 = EXT
J102 = INT
J100 = EXT

I can check my machine later on to ascertain.

EDIT: the card should work fine with your custom chips (DMAC, Ramsey, Buster) and no matter if you have Static Column or Fast Page Mode ZIPs.

:rtfm:

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Thanks for the info. I tried the smell test but didn't come across any stench. Some of the solder pads are NOT shiny but neither do they appear fuzzy. Hmmm...it's hard to tell, really. They're just a little dirty looking but so are a lot of other spots on the board.

That is interesting about the polarity of the caps. I do appear to have them all this way.

If I was more daring and had the time and tools, I may have wanted to replace them but not now.

da9000 wrote:
@jdryyz

OK, I hadn't looked at the posted link in detail (I only saw the A3640 jumper settings). Well, at least I got'em right! :-)

Unfortunately then it sounds like either an incompatibility or a dead A3640.

Here are a couple more things to try:

1) Put up the brightness of your CRT so that it's not black but grayish. Turn on the Ami and note if the color changes to an even lighter gray. If so, the CPU is good. Otherwise, replace the CPU and try again.

2) Assuming in the above test the CPU is good, put your nose very close to the SMD capacitors (5 of them IIRC), and smell them. If there is some nasty stench, they've leaked. Also check to see if their solder pads are fuzzy vs. shiny. If shiny, no leaks. If fuzzy, they've leaked.

3) Desolder and replace the crystal oscillator. It could be dead. Unusual, but it's a possibility. In fact, before you desolder the crystal oscillator, I'd personally get some el-cheapo electrolytic caps and replace the SMD ones. You'll need 22uF @ 16Volts. Here's more info you'll need, because they've been soldered on backwards:
http://amiga.serveftp.net/A3640_capacitor.html


Good luck!

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Thanks for all the help, folks. I have actually returned the card to the party I bought it from. My A3000 will be going up for auction soon also....whenever I get around to pulling off some files and restore the original OS.