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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: dougal on May 23, 2011, 07:38:29 PM

Title: A2000 problems with RAM card
Post by: dougal on May 23, 2011, 07:38:29 PM
9/10 Times my A2000 will not boot if the RAM card is plugged in.

Instead it will either give a RED screen or Green screen or Blue screen or horizontal lines in different colors. Sometimes it will boot and work perfectly addressing the ram and all.

Works all the time without the card.

The specs are A2000 with Rev 4 motherboard, Kickstart 2 and 512 Ram & an A500 floppy drive. The ram card is a Commodore A2058 with i believe 2MB Ram.

Any idea whats wrong?

NOTE: Sometimes (without the ram card) it will boot to a Software Failiure and i will have to press LMB
NOTE 2: If the card is not inserted fully in the zorro slot (i.e not pressed down hard) it seems to work.
Title: Re: A2000 problems with RAM card
Post by: save2600 on May 23, 2011, 08:01:12 PM
Assuming all the RAM chips are good and jumpers are appropriately set, ensure the edge connector is real clean on that board. Same with the female Zorro on the Amiga itself. Failing that, sound like your power supply might be getting weak. Time to replace the caps maybe?
Title: Re: A2000 problems with RAM card
Post by: dougal on May 23, 2011, 09:11:32 PM
Quote from: save2600;639788
Assuming all the RAM chips are good and jumpers are appropriately set, ensure the edge connector is real clean on that board. Same with the female Zorro on the Amiga itself. Failing that, sound like your power supply might be getting weak. Time to replace the caps maybe?


I tried 2 power supplies so i guess it must be the card.

The card looks clean on the edge connector and i tried 3 different zorro slots on the Amiga.

I must note that the Amiga when i bought it was in a terrible state hence it only costed me 35 euros. It was in pieces.

What could i check on the card and amiga?
Title: Re: A2000 problems with RAM card
Post by: Markus_Bieler on May 23, 2011, 10:28:50 PM
Quote from: save2600;639788
...Time to replace the caps maybe?


Or a leaking battery.

Markus
Title: Re: A2000 problems with RAM card
Post by: dougal on May 24, 2011, 10:30:38 AM
Quote from: Markus_Bieler;639819
Or a leaking battery.

Markus


I had removed the battery before it leaked.
Title: Re: A2000 problems with RAM card
Post by: mechy on May 24, 2011, 08:00:21 PM
Check power supply voltages first.
Revision 4 isn't the best motherboard in the world,and i'm not sure if that is your trouble,but upgrading it to rev 4.5+ might help.I remember going rounds long ago with a early 2000 and zorro cards.You could also try swapping buster chips if you have another handy.
Bad or flakey ram may also cause this.next time it boots try copying files to use that ram and see if filling it causes it to crash.
try the easiest stuff first if course :)

mech


Quote from: dougal;639779
9/10 Times my A2000 will not boot if the RAM card is plugged in.

Instead it will either give a RED screen or Green screen or Blue screen or horizontal lines in different colors. Sometimes it will boot and work perfectly addressing the ram and all.

Works all the time without the card.

The specs are A2000 with Rev 4 motherboard, Kickstart 2 and 512 Ram & an A500 floppy drive. The ram card is a Commodore A2058 with i believe 2MB Ram.

Any idea whats wrong?

NOTE: Sometimes (without the ram card) it will boot to a Software Failiure and i will have to press LMB
NOTE 2: If the card is not inserted fully in the zorro slot (i.e not pressed down hard) it seems to work.
Title: Re: A2000 problems with RAM card
Post by: TheBilgeRat on May 24, 2011, 08:57:40 PM
Quote from: mechy;640028
Check power supply voltages first.
Revision 4 isn't the best motherboard in the world,and i'm not sure if that is your trouble,but upgrading it to rev 4.5+ might help.I remember going rounds long ago with a early 2000 and zorro cards.You could also try swapping buster chips if you have another handy.
Bad or flakey ram may also cause this.next time it boots try copying files to use that ram and see if filling it causes it to crash.
try the easiest stuff first if course :)

mech


What's wrong with the rev 4.x boards?
Title: Re: A2000 problems with RAM card
Post by: Zac67 on May 25, 2011, 08:43:19 AM
AFAIR the 4.0 rev doesn't even have a Buster...
Title: Re: A2000 problems with RAM card
Post by: TheBilgeRat on May 25, 2011, 01:29:17 PM
Quote from: Zac67;640116
AFAIR the 4.0 rev doesn't even have a Buster...

Interesting... BBOAH says they all had Busters except for the original german designs.  It looks like the only thing the rev 6 boards add is full ECS.

Found this though : "This final board is a "B2000" Rev 4.3 motherboard, often considered the first "golden" version of the Amiga 2000." - Dave Haynie

So it looks like the mobos pre 4.3 were the ones they were constantly fiddling with...good info to know.
Title: Re: A2000 problems with RAM card
Post by: Zac67 on May 25, 2011, 01:41:21 PM
4.0 is the original German design (A1000 chipset + Zorro backplane).
Rev 4.1 is the first B2000 (A500 chipset + Buster).
Title: Re: A2000 problems with RAM card
Post by: TheBilgeRat on May 25, 2011, 01:55:04 PM
Quote from: Zac67;640166
4.0 is the original German design (A1000 chipset + Zorro backplane).
Rev 4.1 is the first B2000 (A500 chipset + Buster).

Ah, yes, I see that now - they throw the 4.0 into the model "B" section as well, but with a caveat that they never sold them in the US due to a design issue.  Good stuff!

EDIT:  Sorry, Dougal, for getting so off-topic!