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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: amiga4000freak on May 16, 2011, 03:45:23 PM

Title: Fast ram not being detected in amiga 4000
Post by: amiga4000freak on May 16, 2011, 03:45:23 PM

hi to all

I have a amiga 4000 rev b and its not detecting my fast ram.
I have played around with jumpers and nothing happens would it be best to use a zorro 2 card with 4meg of ram or do i invest in a zoram from amiga kit instead so it will be using zorro 3 which is faster. Im only using the amiga for games any suggestions would gratefull

Title: Re: Fast ram not being detected in amiga 4000
Post by: joekster on May 16, 2011, 03:50:36 PM

I have a couple of a4000 in this state. I'm 99% sure its caused by battery leakage (at least in my case).

Title: Re: Fast ram not being detected in amiga 4000
Post by: spaceman88 on May 16, 2011, 04:43:40 PM

Hi,
I also had a couple of A4000 boards with no or intermitant fast RAM. I was able to repair them with a toothbrush and some contact cleaner then cleaned it up with some alcohol. There seemed to be a corrosive reaction between the contacts on the RAM and the contacts on RAM slots. It was worse near the battery so I think that was the source of the problem.

Title: Re: Fast ram not being detected in amiga 4000
Post by: alexh on May 16, 2011, 05:08:22 PM

It could be the wrong type of SIMM. If you've not used these SIMMs before it could be that you need a different configuration of chips (more or less per SIMM)?

I suspect like the others it is more likely to be motherboard battery alkalie damage.

Title: Re: Fast ram not being detected in amiga 4000
Post by: amiga4000freak on May 16, 2011, 07:47:42 PM

hello

yes i have tested two different ram chips an it only detects 2 meg chip ram

Title: Re: Fast ram not being detected in amiga 4000
Post by: alexh on May 16, 2011, 09:32:54 PM

Two different as in two different types with different numbers of chips?

Title: Re: Fast ram not being detected in amiga 4000
Post by: SACC-guy on May 17, 2011, 08:36:24 AM

wasn't four 72 pin page mode 4 meg simms in all four slots or
two 72 pin fast page mode 8 meg simms in sockets one and three
for the sixteen total

Michael