Re: Sirius Ram IIgs Questions

[supertimer@aol.com (Supertimer)]

L Busey <liam1@ix.netcom.com> wrote:

>Does anyone know if 3 chip 30 pin simms compatible with The Sirius IIgs
>ram card? I think I'm need of smaller simms. The simms currently
>installed on my Sirius are so large that they're touching in certain
>areas. I'm afraid that they may be the cause of the flakiness that my
>IIgs has been experiencing lately. So, if someone could point me to an
>outlet where I could purchase low profile 1mb 30 pin simms I'd be most
>appreciative. TIA.
>
>Liam Busey

Liam, from what I've read, if a card (any card) is a tight fit, it is
best to remove the metal shield on the inside of the cover.

>PS. I've heard that on a rom 3 with a Sirius ram card it's best to fill
>all eight simm slots even though the board can only use seven. Is there
>a reason for this?

I've read about this in the FAQ and on csa2 too.  I think it has
to do with the way memory is mapped.  It might be that the
Sirius firmware has problems differentiating the two IIGS
models.  If so, then it may act in a ROM 01 "mode" whatever
IIGS it is in.  That means you will get all memory >256k from
the memory expansion slot (the Sirius).  As you can imagine,
this will cause a 768k memory "hole" somewhere in the 8MB
range.  Add the extra SIMM and the hole fills up.  Some A2
people have reported problems, most notably when copying
files, if only seven slots are filled.  SIMMs are so cheap these
days, it is probably best to leave all eight filled.  You may not
gain 1MB of memory from the IIGS point of view, but you'll
get a stable IIGS without the problems.  In fact, this might be
the cause of your current problem.

Good luck!