View Full Version : A590 - Where to find RAM ?

27th June 2012, 08:03
Yesterday I received my 2nd A590. My other one has 2MB RAM and a 120MB HD but this one has NO ram and NO HD.

I know it needs some sort of 20pin x256 dram chips or something like that but not too sure where to get them and what exactly to look for.

If i search ebay what are the exact words to search for ?

Would i be able to find this RAM type in anything electronic i might have at home ? Maybe an old PC, or computer or anything ?


27th June 2012, 08:57
There should be 16 DIP sockets for 256k X 4 120ns or faster. There should be both an IDE and SCSI interface

27th June 2012, 09:04
I have a faulty Commodore A2052 which is a 2MB Zorro expansion for the A2000. I believe it has soldered Dram chips. By looking at it quickly it seems to have much more than 16 dram chips :(

Would I be able to remove the soldered dram chips from it and use them in the sockets of the A590 ?

The fault it has was that more often than not the A2000 would refuse to boot or else would often freeze and be very unreliable.

27th June 2012, 09:07
And check the ROM version! To use large hard disks to the SCSI connector (up to 4 GB, perhaps to 9 GB), you have to use the version 7 ROMs!

It is possible, that you will get the RAM here at AmiBaY, make a WANTEN thread! ;)

---------- Post added at 10:07 ---------- Previous post was at 10:06 ----------

The A2052 uses 256Kx1 chips! You cannot use them in your A590! ;)

27th June 2012, 09:53
The ROM is 6.1

Thanks I will post a wanted ad

27th June 2012, 10:09
Do you have the service manual?

If you need a pdf, please give me your email address! :)

27th June 2012, 10:09
There should be both an IDE and SCSI interface
XT MFM interface not IDE. Big difference!! The XT MFM interface is an 8-bit forerunner of IDE and practically unusable.

27th June 2012, 10:11
Yes, the A590 uses the 8 bit XT-IDE interface, not the common 16 bit AT-IDE interface! :)

---------- Post added at 11:11 ---------- Previous post was at 11:11 ----------

There should be both an IDE and SCSI interface
XT MFM interface not IDE. Big difference!! The XT MFM interface is practically unusable.

This is not a MFM interface! It is a IDE interface, but only 8 bit wide!

27th June 2012, 10:16
Ok. Stand corrected.

But it's not what you could consider to be "IDE" and needed clarification that it is practically unusable.

27th June 2012, 10:53
The A590 uses 20 pin 256k*4 memory IC's

These are most common on A500 Rev6A / A500+ motherboards as well as the A501 and other 512K / 1MB expansions.

XT- (8bit)-IDE has a 50MB limitation on size with this adapter. Under version 7.0 ROM's it has been reported that 9GB HDD's function, the adapter is also NSD / SCSI Direct compliant as far as I am aware.

27th June 2012, 17:18
I pilfered my ram from a Commodore 2091 board.

27th June 2012, 18:56
OK, we've decided he needs 20-pin 256K X 4 ram that is 120ns or faster; its been determined that the XT-IDE 8-bit HDD interface is lame. Can we reasonably say that a posted thread under Hardware Needed: "20-pin 256K X 4 ram with 120ns access speed" would most benefit the real need?

27th June 2012, 19:40
Now: YES

at the beginning of the thread: NO