My 4 MB extra RAM
 

Have anybody any experience with this 4 MB RAM for the Amiga 1200? (See photo attached).

Is there any way I can test it? In the system where I can see that it is actually working?

Some of my AGA 4MB games won't start.

You can check the board is being seen by the system by check the expansion board section in the early start menu. For the ram, starting workbench you should see the extra fast ram listed in the title bar.

OK. This is what the memory information says. It only says 2 MB. So the 4MB extension it's not working?

The CR2032 battery on the expansion. Could that be the easy fix?

You need to click next there as any fast ram will not show up on that screen (which is showing you the chip ram). Does the card appear in early boot menu expansion section? if it does then you at least know the card is being seen.

Nothing happened when I click next. Just a blink on the screen. Early boot menu expansion section? Where do I find that?

I found it. When I had my extension card in the screen turned yellow when I tried to access the boot menu. I then took out the extension card , and I got to the menu.

Took it out. Cleaned it. Now the yellow screen is gone. And holy smoke!!! It's working 😂😂

Thanks

Still some AGA games that won't start. But the RAM is working at least. Any tricks?

Sometimes it says can't allocate expmem when I try to start a AGA game

Only rather few games need even 4MB of fast RAM. Which titles are you having trouble with?

I shall check what titles that doesn't work later today. I am using a 8 GB memory card with games on.

which games don't work?

I will try some games later today and I will let you know.

If its bigger games, try disabling preload? Might just be running out of memory?

How do I disable preload,?

I disabled magic menu, new icons, smart Win and tools deamon. And now it's working.

Ive just got this error while trying to play Speris Legacy AGA, Ive looked at the ram board and it has 3 jumpers, LK1 4/1Mb or 8/2Mb, LK2 8/4Mb or 2/1Mb, LK3 2Mb or 8Mb. Ive moved the jumpers around and I can get it to report fast ram upto 2Mb or 6Mb but I cant get 4Mb. should I remove a jumper on any of the LK#? I set it up so that I had 2Mb chip and 6Mb fast and I get a 'bad workbench config' (or something similar). Ive restarted my machine and now speris legacy is booting. any ideas what the best set up will be for a fully functional usable 1200?

edit:
Ive found a 4th jumper (INT/CPU) not sure what this is for but it sits next to the empty fpu socket.
Ive played with the configuration of the first 3 jumpers. If I set LK3 to 8Mb I get this config:

Start Address $00200000
End Address $009FFFFF
Total Size 8Mb
Priority 0
Lower Bound $00200020
Upper Bound $00A00000
First Address $0028D2D0
Amount Free $6195976
No. of chunks 103
Expansion Memory

Start Address $00000000
End Address $001FFFFF
Total Size 2Mb
Priority -10
Lower Bound $00000420
Upper Bound $00200000
First Address $000007B8
Amount Free $1780832
No. of chunks 6
Chip Memory

but if I swap LK3 to 2Mb config I get this:
total size 8Mb
First Address $00289410
Amount Free $6196184
No. of chunks 90
Expansion Memory

Lower Bound $00000420
Upper Bound $00200000
First Address $000007B8
No. of chunks 6
chip memory

the number of chunks differs each time I move a jumper either 5, 6 or 7 for the chip ram and 90, 101 or 103 for expanded ram. what do the chunks mean? and what is the best config? I cant get it to use 4mb, it can see its set to use 4mb but WB3.0 only see's 2mb. why?

would it be worth adding a 68882 fpu?

anybody?

Have you tried the software "systest" by Keir? That has a tool to test the RAM directly... not sure if it will help identify the faulty RAM chip?

Yes I ran systest and it ran for a long time and didn't show up any errors.