Re: Using 1 Megabit chips on the IIgs Memory Expansion Card?

["Bill Garber" <willy46pa@comcast.net>]

"Michael Black" <et472@ncf.ca> wrote in message Pine.LNX.4.64.1203312122300.11594@darkstar.example.net">news:Pine.LNX.4.64.1203312122300.11594@darkstar.example.net... 
> On Sat, 31 Mar 2012, D Finnigan wrote: 
> 
>> The Technical Introduction to the IIgs manual states that the 
>> memory expansion card for the IIgs should be able to support 
>> up to 4 MB of RAM when 1 megabit chips become available. 
>>
>> I've never heard of anyone putting 4 MB on this card without 
>> modifying it.   Is what the Apple manual says true? 
> 
> I don't know.  When I filled up my IIGS memory card with 
> extra 256K RAM, I certainly wondered about doing that. 
> I can't remember, though, if it just popped into my mind, 
> or if I saw something concrete to make it within easy 
> reach. 
> 
> It might have even just been that there's so little on 
> the card other than the RAM. 
> 
>   Michael 

Many of them have the first 256K hard-soldered onto the 
card, so, if it is possible, which I don't think it is, 
you'd first need to desolder the first 8 chips. I'm 
looking at one now that has the first 8 soldered in. 

The reason I don't believe that it is possible is, 256kb 
ram chips are 16 pin, while 1mb chips are 18 pin. 

The only modification I've seen is removing all of the 
chips and sockets and installing some 1MB simms by attaching 
them with double sided tape and running a jumper wire for the 
'data', 'address', 'power', 'ground', and the logic lines from 
the card to the simms. Not a job for a novice. 

Why not just buy a card from Briel Computers?, and if he has 
no simms for it, I can supply you with some at little cost. 

SEPA Electronics 
http://www.sepa-electronics.com 
Bill Garber