> We have recently had an old Tandy 4825sx, serial# 002270, model# 25-5142

        I found a link to this system on the Radio Shack web site (Radio Shack's
site is wonderful for older products)
http://support.tandy.com/support_computer/1680.htm

        Or for fax back call (800) 323-6586 and request FaxBack Doc. # 1680

> donated to us. We have no documentation on the system. We intend to use it
> in a small library with a reference encyclopedia CD - dedicated
> to this use.
> It currently has Win 3.1 installed which is fine for this purpose.
> We would like to upgrade the memory from the current 4 megs to 8
> megs which
> will give much better performance under Win 3.1.
> I looked at the motherboard and it takes 30 pin simms and there
> are 9 chips

        Sounds like parity SIMMs.

> to a simm. There are 8 slots and 4 slots are empty.
> I could not find any info at Radio Shacks web site about the unit.
> In searching for memory I found listed:
>      1meg - 1*9 - 60ns, 70 ns, and 80 ns
> Is this the memory that I would need? And can we just go with the fastest
> memory? Is parity and non-parity and issue or is this all parity

        Well, speed wise, fastest is often the wisest choice (there are
exceptions). Memory can be very finicky, I recommend you get as close as you
can to the type of memory you currently have. My guess is the system uses
80ns or 70ns memory, getting 60ns shouldn't cause a problem. Do get parity
though, some systems choke when you put in non parity and parity SIMMs. In
any case, buy from a place that will let you return the memory, I have one
486 system which is very picky when it comes to memory, some 4MB 30 pin 9
chip SIMMs work fine, others with the same specs don't.

> memory? Also,
> I understand that the memory has to be added in banks of four? Is
> that correct?
> (I have never bought these older simms before)

     With Intel 486 processors, yes, they required 30 pin SIMMs in banks of
four. Hope this helped, TTYL

                         PCBUILD's List Owner's:
                      Bob Wright<[log in to unmask]>
                       Drew Dunn<[log in to unmask]>