STRam Only seeing 2048k

I just installed one of these into a brand new old stock Atari 520 stm board (Rev h) and it’s only seeing 2048k. For it to be stable I have to leave RAS disconnected. If connected then the TOS menu and text is garbled and the machine crashes when launching an application. At one point I managed to get it to load sysinfo while RAS was connected but it still showed only 2048k.

Any ideas what could be the issue here?

Sep 24 '23 11:09 sideburn

Had a similar issue on a Rev H motherboard. I found swapping CAS1L/CAS1H fixed it.

https://forums.atariage.com/topic/360236-atari-520st-4mb-agranlund-stram-expansion-notes-from-an-install/

Jan 28 '24 16:01 oraclejedi

Had a similar issue on a Rev H motherboard. I found swapping CAS1L/CAS1H fixed it.

https://forums.atariage.com/topic/360236-atari-520st-4mb-agranlund-stram-expansion-notes-from-an-install/

Thanks I will have look. ** Yep! That was it. Swapped them and reconnected RAS and now I've got the full 4MB. Thanks!

Jan 31 '24 05:01 sideburn