[comp.sys.mac.hardware] 9-bit SIMMs for Macs

cho@aber-cs.UUCP (C.H. Orgill) (07/23/90)

A local dealer says he can beat U.K. SIMM prices by supplying 9-bit
SIMMs instead of the 8-bit ones.  Apparently the 9-bit SIMMs fit in
something called a PC :-) so the pricing is more aggressive. I looked
inside my SE and lo, the 8-bit SIMM cards have unused holes and
tracking for an extra chip. Does the motherboard just not run tracks
to the extra bit ? Will they work o.k. with just a little more heat or
is the SIMM interface more complex ?

Regards,

Chris Orgill,				tel +44 970 622447
Research Associate,
Computer Science Department,		 cho%cs.aber.ac.uk@uunet.uu.net (ARPA)
University College of Wales,		 cho@uk.ac.aber.cs (JANET)
Aberystwyth, Dyfed, United Kingdom. SY23 3BZ.

jdevoto@Apple.COM (Jeanne A. E. DeVoto) (07/24/90)

In article <1969@aber-cs.UUCP> cho@uk.ac.aber.cs (Chris Orgill) writes:
>A local dealer says he can beat U.K. SIMM prices by supplying 9-bit
>SIMMs instead of the 8-bit ones.   [...]    Will they work o.k....?

They should work fine. The Mac circuitry just ignores the line from
the parity (9th) chip on the SIMM.
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cantie@acsu.buffalo.edu (bruce n cantie) (07/24/90)

>A local dealer says he can beat U.K. SIMM prices by supplying 9-bit
>SIMMs instead of the 8-bit ones.  Apparently the 9-bit SIMMs fit in
>something called a PC :-) so the pricing is more aggressive. I looked
>inside my SE and lo, the 8-bit SIMM cards have unused holes and
>tracking for an extra chip. Does the motherboard just not run tracks
>to the extra bit ? Will they work o.k. .......

They will work just fine, atleast I hope they do, I have 8 Meg 
worth in my Mac II!






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