14 Dec
2011
14 Dec
'11
10:07 p.m.
On Dec 14, 2011, at 4:33 PM, Cameron Kaiser wrote:
There is some dispute over total memory. LowEndMac,
which I tend to believe
more, says that 128MB SIMMs have been used up to a maximum of 132MB. However,
it is known that double-banked 64MB SIMMs won't work, and I would be very
cautious about 128MB SIMMs. My unit has 32MB in it for a total of 36, which
is the stated maximum (and the maximum for the LCIII that preceded it, for
that matter) and the maximum that EveryMac says. So I'd be careful about
going higher or you may be buying duds.
Well, I gave it some thought. You really can't do 128MB in a 72-pin SIMM without
double-banking it; there are only 12 address lines on the SIMM, which gives you 24 bits of
address space (16Mx32 = 64MB) per bank. It may be that the 64MB double-banked ones
don't work right because they'd need memory parts with a non-square array or some
such; might be worth disassembling the ROM and seeing what the diagnostic is trying to do
one of these days.
In any case, it's only $20 with free shipping on Ebay, so it's not a very
expensive experiment.
The Q605 is an underappreciated gem, especially with a
full '040. Mine ran
NetBSD exceptionally well until I merged its functions into the POWER6. Now
my only '040 left is the Mystic Color Classic.
The LC475/Quadra 605 is probably my favorite machine from the '040 era (the SE/30 and
IIsi vie for my '030 affections). I wish I had one with a Q605 case, because I think
it looks a bit nicer; as it is, the fellow who sold me his 475 very nicely included an
ImageWriter II, but didn't bother to pack it very well. ImageWriter IIs are HEAVY.
So the case is almost perfunctory at this point. Always wanted to make a rackmount case
for it some day... All the LCs (the normal ones, anyway) have a very similar form factor,
so it's the sort of thing that would be useful across the line.
I get my old RAM from MemoryX. They're not the
cheapest, but I've never got
a bad one from them, and they're relatively local (Santa Clara Valley).
The one on WeLoveMacs indicated for the Q605 is definitely a double-ranked one (look at
the picture, which looks to be a picture of the actual item):
http://www.welovemacs.com/apple-memory-performa-performa-578-128mb-72pin-ma…
I guess I'm not terribly worried about it.
- Dave