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PedeFUP
4th September 2012, 21:34
Hi there.

I have an Amiga 4000 desktop that have followed me for several years. It has been running flawlessly for a couple of years, but it has been on my shelf for the last year or so. Recently I took it down and tried booting it, but no such luck.

So here goes, I have tried A LOT of things with it now, but it still won't boot.

When I turn on the machine, sometimes it will change the light of the power LED as it is going through post-boot, and then it will flash (crash). Other times it will just sit there. It never actually boots.

So I stripped it down to basic hardware. No Zorro cards, not harddrives and that kind of stuff.
Then I found an old C= 3400 '030 CPU card and stuffed it into the machine, then it boots.
I take out another A4000 and put the Cyberstorm into that machine, where it works.
So it is the first A4000 that doesn't work with the Cyberstorm MK II '040.

What else have I tried:
Cleaning the different slots.
Different RAM configurations, even no fast RAM at all on either accelerator and motherboard.
Reseating the chip RAM block, I can't even get the green chip ram failure.
Reseating every chip on the motherboard including the ROM's.
Tried both with and without the SCSI controller.
The PSU has been measured to provide the correct +5 and +12V.
We googled some tips on measuring on the C188, and cleaned out the powerplug for the motherboard, C188 now measures 4,939V steady.
A friend resoldered a couple of dodgy looking solderings of the backside of the motherboard, and cleaned everything out around the accelerator connector.

To recap shortly. The first A4000 doesnt work with the Cyberstorm, but with the C=3400. The second A4000 DOES work with the Cyberstorm.

(The second A4000 is almost vanilla, and has almost never been used as I found it from a stock after a company had closed, I would like to keep it vanilla)

The next thing I want to test is another accelerator card, preferebly another Cyberstorm MKII.
Hopefully another friend can help with this.

However, I would LOVE to get any input from you guys, what else should I try?

Thanks :)

Cheers. Pede.

J.T.Kirk
4th September 2012, 21:39
There is a jumper setting on the motherboard, to switch EXT(ernal) and INT(ernal) CPU cards. Check if the jumper is set in the same position on both A4000.

AndyLandy
4th September 2012, 22:12
There is a jumper setting on the motherboard, to switch EXT(ernal) and INT(ernal) CPU cards. Check if the jumper is set in the same position on both A4000.

Both the A3630 and the Cyberstorm MkII require J100 and J104 to be set to INT, so no jumper fiddling should be required. Still, it's always worth double-checking they're set right.

:thumbsup:

PedeFUP
5th September 2012, 12:11
That one should be on the "Tried list" as well.

As Andy stated both cpu cards need the same jumper setting, but I have also tried setting it to EXT. Still doesn't work.
I don't think a cpu crash should be able to happen if the jumper were in the wrong position.

Cheers. Pede.

fitzsteve
5th September 2012, 12:14
Can you check any socketed chips are seated correctly such as buster (this one is the highest cause of you issue IMHO)

Replacing any leaked capacitors might also help, Hikey on these boards refurbishes A4000 Motherboards, he done my A4kT Mobo and it is like new :)

Good luck!

Steve.

PedeFUP
6th September 2012, 14:06
Reseating the chips is allready on the tried list.

I'll look into the capacitor thing.

Keep the suggestions comming, please :)

Cheers. Pede.