[geeks] Anyone know of good sources of 5V DIMMs?

[nate at portents.com]

> How old? In order to run OS X 10.2 or later, you need to have a G3
> processor.

7300/7600 class machines upgraded with G3 processors from 250Mhz to
500Mhz.  Video cards will be Radeon 7000 32MB PCI, and hard drives are
going to be new 9GB low profile SCSI drives.

> IMHO 10.0 and 10.1 are not worth running because they were to limited
> in function and buggy, 10.2 is not because any recent programs that
> are available were compiled under 10.3 and won't run on anything older.

I'm aiming at 10.3 with XPostFacto.

> Some things, such as the latest such as Mplayer binary, iLife'06, many
> functions of Garage Band '05, won't work with a G3 processor anyway.

They won't need those, just MS Office type stuff, web, and email.  No
multimedia stuff needed.

> There are other problems for example, for example  Blue and White G3's and
> older (beige) G3's, early iMacs, etc won't support an IDE drive bigger
> than
> 12 gig for most brands and 20 for a few Maxtor ones. It's not a size
> limitation, it's a hardware bug in the IDE controler chip and they
> can't keep up with the drive.

That's only an openfirmware IDE driver issue, except the Rev A B&W which
had some IDE controller chip issues.  The beige G3 Macs can take an IDE
drive as big as 128GB, you just have to keep your OS X partition to 8GB or
less and at the beginning of the drive.  After the OS is booted, it's own
driver takes over and can handle partitions above 8GB just fine.

I also have PCI IDE cards which, having their own openfirmware drivers,
don't have the 8GB limitation for booting.

> 10.3 and 10.4 work well with 256m of RAM. Note that many older machines
> will not support more than 256m of RAM unless you turn of cache at boot
> time (an X-PostFacto option). Once they are booted the cache is turned
> on, so it is ok.

The G3 upgrade cards won't have their caches turned on until OS X boots,
so I don't think it will be a problem.  They have 8 DIMM slots, so they
can take up to 1GB of RAM, and I'm still hoping to get them to 512MB per
machine if I can do it inexpensively enough.

> AFIK all of the machines that actually run OSX use 3.3 volt memory.
> Be careful not to mix speeds and registered versus non registered memory.
> B&W G3's and older will can not address more than 128m chips, so a 256m
> DIMM/SODIMM must have 16 chips instead of 8 or it will only be a 128m.

Wish they actually had something as new as a B&W.  If I'm lucky, I'll be
piecing together a gigabit G4 from parts soon that I can donate to them,
and that will probably be their one 'modern' machine.

> ...
> If you do get an iMac, Pismo, Lombard  or desktop with USB ports, keep
> in mind that the ports are only USB 1, and they are not bootable. VIA
> chipset USB 2 cards don't work properly, they will work with keyboards
> and mice, but not disk drives. If you do upgrade the USB ports, you will
> need NEC chipset cards. (neither are the firewire ports, and some PCI
> SCSI cards)

I've been investigating USB PCI cards actually, and I found out that VIA
actually makes drivers for their USB 2.0 cards for OS X.  I haven't tried
them yet, but you can get them from here, and I wouldn't be surprised if
they fix the USB storage device issues you're talking about:

http://www.viaarena.com/default.aspx?PageID=420&OSID=23&CatID=2470&SubCatID=122

Description says it's for OS X 10.2-10.4, for VT6202 and VT6212 chipset
cards.

But I'm not too concerned about USB, as their printer is on ethernet, and
I think I can scrounge up some multibutton ADB mice from Kensington which
have OS X drivers (Kensington was the only company to write ADB drivers
for OS X), though they won't have scroll wheels, so I might end up going
the USB card route in the end.

- Nate