>Subject:     Re: Quadra 605
>Sent:        15/4/97 7:09 pm
>Received:    15/4/97 11:25 pm
>From:        Bob Nestor, rnestor@metronet.com
>To:          Jonathan Lyons, lelsoft1@mail1.nai.net
>             CAGNARD Paul-Jean, cagnard@iishp1.unil.ch
>CC:          port-mac68k, port-mac68k@NetBSD.ORG
>
>>The Quadra 605 is _exactly_ the same as the Performa 475...as a matter of
>>fact, my Quadra 605 has the name "Macintosh Performa" imprinted on the
>>front.
>
>The Gestalt ID for the Quadra 605 is 94 and the Gestalt ID for the 
>Performa 475 is 89. So at this level the two are not _exactly_ identical 
>even if you change the faceplate.  If you dig a bit deeper into the ROMs 
>you'll find that although the two share many common routines, they use 
>some different sequences for ADB interrupt handling.  From a NetBSD point 
>of view, if your Kernel is built on the MRG routines, the two systems are 
>not _exactly_ the same, but very similar.

This is not true.  There's a jumper, on the Q605's logic board, that if 
present, makes Gestalt report the machine is a Q605.  If it's missing, 
the machine reports itself as an LC 475. These machine are _completely_ 
identical, and use the same ROM rev, and hardware.  The only difference 
are the nameplates, the cases and the presence of this jumper at J118. I 
have installed this jumper on my own LC 475, to test it, and it is true.  
Under System 7.1, my LC 475 will report itself as a Q605.

This is from www.violet.berkeley.edu/q605.html:

The Quadra 605, LC475, P475, and P476 use the same motherboard. A jumper 
in the front right hand corner, J118, differentiates the Quadra 605 and 
LC475. The Performa 475 and 476 are the same as the LC475. If the jumper 
is installed, it is a Quadra 605. If the jumper is not, it is a LC475. 
The system and other software know this from what is called a gestalt. 
The gestalt is a number that is specific to each type of Mac Apple makes. 
A Quadra 605 is gestalt 94 while a LC475 is gestalt 89. There are several 
unassigned gestalts, and this modification will explain a few of them: 

Steve