[comp.sys.mac.hardware] Mac Plus memory upgrade

jay@void.lockheed.com (Jay Weber) (06/11/91)

Forgive me if this is an oft-asked question, but does someone remember
how to boost a Mac Plus from 1 -> 2.5 Meg?  I have two 1 Meg SIMMs, do
they go in particular slots?  Most importantly, I heard a rumor that
one must also clip R8 (R9 is missing), labeled "256K Bit" -- can someone
confirm this before I do it?

Thanks, Jay

Jay Weber
jay@laic.lockheed.com

derosa@motcid.UUCP (John DeRosa) (06/12/91)

jay@void.lockheed.com (Jay Weber) writes:

>............................  Most importantly, I heard a rumor that
>one must also clip R8 (R9 is missing), labeled "256K Bit" -- can someone
>confirm this before I do it?

According to the manual that I got with some chips from Technology
works (great manual!), here is what you must do;

"Locate the R8 resistor in the corner of the motherboard 
nearest the Printer Port; clip it on one end and bend
it aside to prevent contact.

DO NOT REMOVE IT, so that you can later reconfigure your
Mac Plus back to 1 MB if necessary.  If R9 is in place,
it will also need to be clipped.  It is only used if
your machine is configured as 512kb or 2MB."

SIMM Configuration

Row 1 (SIMMs 1 & 2) - 1 meg simms
Row 2 (SIMMs 3 & 4) - 256 k simms

-- 
= Enjoy!                                                                   = 
=          John DeRosa, Motorola, Inc, Cellular Infrastructure Group       =
= e-mail:    motcid!derosaj@uunet.uu.net, n1111@applelink.apple.com        =
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