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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: dingebre on February 24, 2025, 08:36:58 PM

Title: Amiga A4000 Fast and Chip RAM
Post by: dingebre on February 24, 2025, 08:36:58 PM

Maybe I am unable to find a straight answer because it should be obvious, but I'm at a loss. I am fleshing out an A4000 "Re-Amiga" and
I would like some information regarding A4000 Fast and Chip RAM.

I read the manual. I searched the forums. I searched YouTube. I searched the internet in general. I am still confused.

I found some information here:
https://www.scuzzscink.com/amiga/amiga_scuzz49.htm
http://amigadev.elowar.com/read/ADCD_2.1/AmigaMail_Vol2_guide/node0162.html

Based on part numbers from the "amigadev.elowar.com" web site document, I found some suitable 4 MB Micron Non-Parity Memory 1Mx32 MT8D132M-7, 70 ns SIMMS (as opposed to the Micron MT8D132M-80 80 ns on the document) which I understand will work for the Fast RAM. Can I use one of these for 2 MB of Chip RAM?

Thank you!

David

Title: Re: Amiga A4000 Fast and Chip RAM
Post by: Castellen on February 25, 2025, 07:40:48 PM

If you use anything except a 2MB double sided SIMM, you'll only get 1MB chip memory instead of the expected (maximum) 2MB.

The correct SIMMs can be hard to find.  I got sick of constantly trying to locate and purchase used SIMMs in unknown condition, and fixed the problem by designing my own.
 I've got stock available if you can't find them elsewhere:
http://amiga.serveftp.net/inventory.xgi - see part number SIMM72, 2MB DS

Title: Re: Amiga A4000 Fast and Chip RAM
Post by: dingebre on February 26, 2025, 01:10:54 AM

You're amazing! I have 3 A4000Ds. Two Re-Amigas, and one vintage. I sent an email from your web page.

Thank you!

David

Title: Re: Amiga A4000 Fast and Chip RAM
Post by: zipper on February 26, 2025, 05:25:27 PM

What about using 8 MB SIMM as Chip Ram?