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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: theformula on December 12, 2007, 12:51:12 PM

Title: Rebuilding A4000 need advice
Post by: theformula on December 12, 2007, 12:51:12 PM
Hi i am currently rebuilding me amiga collection. I have 3 a4000's I have been trying to get the kickstart screen (one with disk animation) for some time. I am not sure what components need to be added to the board before i should see that screen. I have tried with adding zorro board and disk drive with cpu (i have tried my 030 and 060) all I seem to get is a green screen when I run one of my motherboards with the 030 cpu. Thats about all I can get out of them :(

I was wondering if I am doing it wrong. I have seen them all working well before and the batteries have been replaced. I am stuck. Was wondering if somebody could list what i need running to get the screen and what my problem might be.

Thanks
Title: Re: Rebuilding A4000 need advice
Post by: motorollin on December 12, 2007, 12:54:13 PM
You don't need anything connected to get the Kickstart screen. A green screen means bad chip RAM or Agnus, so check they are all seated properly and if possible swap them out from a known working machine. Also, make sure the jumpers on the mobo are correct for the CPU board you're using.

--
moto
Title: Re: Rebuilding A4000 need advice
Post by: Slash on December 12, 2007, 12:56:05 PM
Do you have 2Mb of Chip RAM installed in the 5th SIMM slot on the motherboard? (The one furthest away from the edge of the board, nearest the Zorro daughterboard).
Title: Re: Rebuilding A4000 need advice
Post by: theformula on December 12, 2007, 12:56:39 PM
thanks dude i am noob when it comes to 4000's I will give that a try :D
Title: Re: Rebuilding A4000 need advice
Post by: theformula on December 12, 2007, 01:15:44 PM
I was wondering how long the wait is until the screen appears is it like a minuite or a few seconds and is there anything else i need to do?
Title: Re: Rebuilding A4000 need advice
Post by: motorollin on December 12, 2007, 01:19:37 PM
Depends on the version of Kickstart. For 3.1 it's around 30 seconds. For 3.0 it's a bit less than that. There's nothing you need to do. If the screen is any colour other than black during this delay, then something is wrong. If it stays black, then something is wrong. If it pauses for around 30 seconds on the black screen then shows the Kickstart screen, then this is fine.

--
moto
Title: Re: Rebuilding A4000 need advice
Post by: theformula on December 12, 2007, 02:48:01 PM
Grrr its doing my head in lolz.

I have taken some pictures just incase there is anything blatent you can spot.

Whole motherboard
http://img155.imageshack.us/img155/9830/sa000023od2.jpg

More detailed
http://img155.imageshack.us/img155/4003/sa000025ki9.jpg

http://img155.imageshack.us/img155/9597/sa000026iw2.jpg

Sorry about my crazy meathods but i am a total Noob when it comes to hardware  :-P  if you want pics of the jumpers just ask as I have not got a clue what I am doing  :lol:
Title: Re: Rebuilding A4000 need advice
Post by: Wol on December 12, 2007, 02:54:06 PM
It might be a good idea to fit a Processor Card,
in your photos there is no card present; therfore
NO Processor...


It plugs in the Fast Slot...;-)



Wol.
Title: Re: Rebuilding A4000 need advice
Post by: theformula on December 12, 2007, 05:04:53 PM
fixed it :D I had to change the jumper on the rom speed. I am so happy now ty for your help guys :D :D :D
Title: Re: Rebuilding A4000 need advice
Post by: da9000 on December 14, 2007, 11:12:27 PM
Are you still getting green screens?

Assuming you've done what the guys above have said (insert CPU card, reseat socketed chips, make sure RAM chips are good by testing on another machine), then one further reason for a green screen could be a leaking SMD capacitor near the battery (speaking of batteries, I'd remove those ASAP, because they will kill your motherboard one day, almost certain). After cleaning up the blown capacitor and replacing it, it worked like a charm again. In fact it'd be a good idea to replace all SMD caps on those motherboards. They will leak eventually, and even if you can't see it, they might be leaking already. I've replaced all mine with tantalums and won't have to worry for 100+ years (wait - I'll be dead then!) :)

Good luck!

PS. if you need more info, contact me
Title: Re: Rebuilding A4000 need advice
Post by: gdanko on December 14, 2007, 11:23:02 PM
Quote

theformula wrote:
I was wondering how long the wait is until the screen appears is it like a minuite or a few seconds and is there anything else i need to do?


If there is no IDE devices connected the delay is a bit long. Upto a minute or two.
Title: Re: Rebuilding A4000 need advice
Post by: scuzzb494 on December 15, 2007, 12:02:30 AM
Hi

When I upgraded my A4000 from the 030 to the 040 I not only had to add two extra support pins to the processor board but also set the jumper at J100 Clock90 source to 2-3 External 040 and also Jumper at J104 CPU clock source to 2-3 External. I also changed Jumper at J151 to 1-2 200NS. That support of the processor can be very important and seating is everything. Also there can be issues with the general support of the motherboard in the casing. Mucking around with differing boards does need an element of care really... so I would check all the jumpers for the various board configurations. I would also check the seating of the ROM chips.

Its just that you may think its to do with jumper settings, but by taking stuff out and putting it back in you actually cure the problem by other means. i.e. by actually seating the processor board along its full length properly. Those plastic support legs are quite important.

I had a terrible problem with a Cyberstorm earlier this year with this very same problem.

scuzz