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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: chfriend on August 23, 2014, 08:22:12 PM

Title: Amiga 3000 driving me crazy
Post by: chfriend on August 23, 2014, 08:22:12 PM
Every few months I have to complete tear down my 3000 and reseat everything to get it to work.  This time it was the flashing green screen of death, which after taking everything out and narrowing it down, appeared to be caused by the Warpengine 3040 even though it's screwed down to the posts.  In the past it's been the graphics card (I still get occasional graphics corruption on the graphics card and I have to take off the cover and play with it in the slot to stop it).

What is the best thing to use to give the connectors a good cleaning without risk of damage?  Spray electrical cleaner?
Title: Re: Amiga 3000 driving me crazy
Post by: carvedeye on August 23, 2014, 08:35:11 PM
Quote from: chfriend;771584
Every few months I have to complete tear down my 3000 and reseat everything to get it to work.  This time it was the flashing green screen of death, which after taking everything out and narrowing it down, appeared to be caused by the Warpengine 3040 even though it's screwed down to the posts.  In the past it's been the graphics card (I still get occasional graphics corruption on the graphics card and I have to take off the cover and play with it in the slot to stop it).

What is the best thing to use to give the connectors a good cleaning without risk of damage?  Spray electrical cleaner?


You could try cleaning the contacts?
Title: Re: Amiga 3000 driving me crazy
Post by: Lurch on August 23, 2014, 09:08:14 PM
Just use an eraser and gently rub up and down on the contacts. The best brands/type are the Magic Rub or the Pink Pearl.

Work great.
Title: Re: Amiga 3000 driving me crazy
Post by: chfriend on August 23, 2014, 09:43:58 PM
Quote from: Lurch;771590
Just use an eraser and gently rub up and down on the contacts. The best brands/type are the Magic Rub or the Pink Pearl.

Work great.


I've done that. The problem is that doesn't work on the female Zoroaster connectors or either of the fast slot connectors because you can't get the eraser in it and I think that's where the problem lies.
Title: Re: Amiga 3000 driving me crazy
Post by: magnetic on August 23, 2014, 10:33:16 PM
The fast cpu slot on a3000/4000 can cause failure if boards have been plugged and unplugged alot or through shipment/ torqueing boards etc.

Are you sure your psu is ok? I'm saying that because you mention the gfx board having problems too?
Title: Re: Amiga 3000 driving me crazy
Post by: esc on August 23, 2014, 10:36:29 PM
I've used a q-tip with rubbing alcohol in the past. You'll want to make sure none of the cotton residue is left behind, though. It's a pain in the neck.
Title: Re: Amiga 3000 driving me crazy
Post by: magnetic on August 23, 2014, 10:40:28 PM
Just re read your post Green screen afaik is the agnus chip.
Title: Re: Amiga 3000 driving me crazy
Post by: TeamBlackFox on August 23, 2014, 11:12:04 PM
Take some 90% isopropanol, put some into a dish. Take a clean toothbrush and scrub the CPu slot, Zorro and chip sockets. These machines are oxidizing all the time and a toothbrush and alcohol should take care of most of it.
Title: Re: Amiga 3000 driving me crazy
Post by: narcea on August 23, 2014, 11:12:27 PM
The industry standard way of cleaning contract is with IPA aka isopropal alcohol the stronger the better. Look for 99%. You use this with a natural hair brush. Like a horse hair acid brush. Using esd protection you rinse brush and rinse again. Blow dry do not let air dry. You can use lint free cloths for the fingers instead of a brush.

Never use an eraser it'll leave behind a film and is abrasive. It'll cause problems eventually. This is how it's done at IBM and most other companies. If you can't get 100% IPA then 97 will suffice.

I used to have problems with the daughter board not seating properly in my 3000.
Title: Re: Amiga 3000 driving me crazy
Post by: magnetic on August 23, 2014, 11:15:48 PM
Alot of times its not the cpu slot is dirty its that from wear and tear its not making enough contact with the cpu card. In this case it needs to be replaced. I highly doubt cleaning it with IPA will fix it...
Title: Re: Amiga 3000 driving me crazy
Post by: CJK3o3 on August 23, 2014, 11:22:32 PM
In most cases it's oxidation. Alcohol is not always a good idea, it will clean the traces but can do more damage to the already worn material. With my amigas I used Deoxit - it does leave a very thin film on the traces but does not damage them. I wouldn't recommend any stronger stuff on old mobos.
Title: Re: Amiga 3000 driving me crazy
Post by: matt3k on August 23, 2014, 11:58:09 PM
I have been radio shack circuit cleaner for 25 plus years on my 3k and it works great.

Give it a shot and reseat the chips...
Title: Re: Amiga 3000 driving me crazy
Post by: Acill on August 24, 2014, 12:46:32 AM
Take some very fine sand paper and put in over the edge of a card edge.  Press it in and out a few times and polish the contacts. Then use a circuit cleaner and canned air to blow out any dust.

You must get the dust out completely. If that scares you get a very thin line free cloth or felt from a craft store and do the same soak it in cleaner.
Title: Re: Amiga 3000 driving me crazy
Post by: Jeff on August 24, 2014, 02:11:15 AM
Perhaps the capacitors are failing in the power supply and the voltage and or current isn't stable. Are the system temperatures under control? Some old analog video equipment I have and maintain is difficult to run unless the power at the outlet is stable too.
Title: Re: Amiga 3000 driving me crazy
Post by: danbeaver on August 24, 2014, 02:17:15 AM
While the eraser removes oxidation and dirt, one does need to clean afterwards with Iso-PrOH; the concentration most commonly available is 91%, but the 9% water is an Azeotrope and using a higher concentration of IPA means another chemical such a benzene has been added.  This is fine for chemical reaction in a lab, but the alcohol pulls away the water molecules as it evaporates.  So anything above 91% is a waste of money (thank you, IBM).

The freshly cleaned contacts only need a protection layer if copper or tin; gold contacts do not, as gold does not oxidize.  

That being said, the A3000 is the most beautiful of the Amigas, but one of the worst designed: sharp steel metal edges, D800 fiasco, ZIP memory insertion, 25-pin SCSI connector above another identical 25-pin parallel port, INT2 issue, requirement of daughter board to be in place to boot, flawed WD SCSI controller (8 revisions to get it to work?), and a complete lack of drive space -- CDROM & second HDD.  After bleeding to the point of anemia restoring two, I sold them never to return. In my opinion only!

http://en.m.wikipedia.org/wiki/Isopropyl_alcohol
http://gold.yabz.com/facts.htm
Title: Re: Amiga 3000 driving me crazy
Post by: magnetic on August 24, 2014, 04:47:59 AM
Quote from: Jeff;771619
Perhaps the capacitors are failing in the power supply and the voltage and or current isn't stable. Are the system temperatures under control? Some old analog video equipment I have and maintain is difficult to run unless the power at the outlet is stable too.


I agree with you sounds like psu problems cleaning the slot prolly isnt going to help.
Title: Re: Amiga 3000 driving me crazy
Post by: chfriend on August 24, 2014, 05:54:32 PM
I'm starting to wonder if it's the PSU as well.  I just got it back together with no expansions and at first got a green screen with constant reboot, followed by a white screen and then it booted.  The other thing that happens is until the computer warms up the Amber output is fuzzy unless I play with the back video adjust control.

Anyone know of a suitable replacement?  Unlike the 2000 which can take a standard AT/ATX supply without much, if any modification, the 3000 is completely proprietary regarding the form factor.

In fact, IIRC a 1hz reboot indicates a problem with the power supply tick signal.