Would you pay $100 for 8MB RAM?

[orcish75]

Excellent! Glad you got it working. Supreme hackery there! :lol: I love seeing success stories like these..

[Ral-Clan]

Excellent! Glad you got it working. Supreme hackery there! :lol: I love seeing success stories like these..

Thanks!  Also thanks again for the tip about using the DIP sockets as adapter bases.  If you hadn't mentioned that I would still be waiting for the parts from Digikey to start this project.

The only question I would have for anyone who can answer, is why does my Amiga start up sometimes with the RAM fragmentation seen in the mem test screenshot above. Notice that there are three small RAM blocks at the end of the RAM list?

Then at other times (like this morning when I turned it on to start testing) I get less fragmentation (i.e. one large almost 8MB block, the 2M chip RAM block, and just one other small ram fragment as well).

I do recall I made one change since yesterday and today - I put an icon that was "left out" on the desktop "away".  I wonder if this can fragment RAM during boot.

[Ral-Clan]

Just an observation and note of caution to anyone installing RAM on an Amiga (or doing a project like this):

Although I thought I was done this project, and the RAM had passed multiple test cycles in Advanced Amiga Analyzer, I got a couple of strange Gurus.  I then noticed that they occurred when I was opening a program or writing to the RAM disk.

So....I decided to fill up the RAM disk to the maximum 8MB installed on the system (I basically started copying the contents of my hard drive to the RAM disk).

Sure enough - BAM - at a certain point I would always get a GURU.

I did some tests and chip swapping and found two chips with bad solder joints - THESE CHIPS HAD PASSED THE RAM TEST.

Once the solder joints were repaired, the chips worked well with a similar test of filling up the RAM disk - no GURUs (they also pass the Analyzer tests).

So, it's wierd.  I wonder why a RAM diagnostic test wouldn't catch this particular problem, but only writing actual files to the RAM will.

Anyway, it's something important to note for anyone trying this in future.

[bbond007]

Although I thought I was done this project, and the RAM had passed multiple test cycles in Advanced Amiga Analyzer, I got a couple of strange Gurus.  I then noticed that they occurred when I was opening a program or writing to the RAM disk.

do you know what testing mythology the ram checker used? my guess is its not very good

like for example, if you just write a random number to every byte and read it back, that not a very good method as it does not test every bit.

[Ral-Clan]

It's Advanced Amiga Analyzer which is a fairly well respected diagnostic software package (or so I thought).  It has detected bad RAM in other cases.