All the IIfx ram I have and have seen were 9 chip (1MB and 4MB SIMMs). I
think the 16MB SIMMs were very tall and had more then 9 chips on them like
the ones in the picture below.
http://www.mathdittos2.com/columns/bh/bh990511.html
The machine pictured has 68MB of ram (4x16MB plus 4x1MB). 128MB is the
maximum ram available. It looks like the 16MB SIMMs in the picture have 36
chips on them (probably the same chips that make up the 4MB part just 4
times as many).
I Hope this helps.
----- Original Message -----
From: "Eric J Korpela" <korpela at ssl.berkeley.edu>
To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org>
Sent: Thursday, September 29, 2005 5:01 PM
Subject: Re: Tristate Buffer Output if Input is High-Z?
I also notice that the table on page 2 of the technote contradicts the IIfx
section. The table says you can put up to 128MB in a IIfx, but the IIfx
section says the biggest SIMM allowed is 256kx8.
Eric
On 9/29/05, Eric J Korpela <korpela at ssl.berkeley.edu> wrote:
Anyone have a datasheet for Hitachi HM511000AJP8 DRAMs? It's used in at
least some IIfx SIMMS.
What's the deal with parity on the IIfx? Is the parity bit stored off the
SIMM? The technote
http://developer.apple.com/technotes/hw/pdf/hw_25.pdfmentions
parity, are
there 9-chip SIMMS on the IIfx? Or is the parity stored
on a separate RAM on the mainboard? Since your max
memory is 8x(4Mx8bit
bit
SIMMS) accessed 32 bits at a time (I assume) you'd
only need 1 Mbit of
parity RAM if you do parity across 32 bits.)
Eric