From: ubs@carson.u.washington.edu (University Bookstore)
Subject: Re: Why does Apple give us a confusing message?
Article-I.D.: shelley.1qs4fjINN74f
Organization: University of Washington, Seattle
Lines: 37
NNTP-Posting-Host: carson.u.washington.edu

In article <C5nGII.BGx@news2.cis.umn.edu> bunt0003@student.tc.umn.edu (Monthian Buntan-1) writes:
>
>Hi there,
>
>Does anyone know why Apple has an ambiguous message for
>C650 regarding fpu?  In all Mac price lists I've seen, every C650
>has the message "fpu: optional".  I know from what we've discussed in this
>newsgroup that all C650 have the fpu built in except the 4/80
>configuration.  Why would they be so unclear about this issue in their
>price list?
>I'm planning to buy the C650 8/230/cd pretty soon, but I'm now getting
>confused with whether it comes with fpu or not.
>Why say "optional" if it's built in?
>Please, anybody help me understand this game.
>
>Regards,
>
>Thian.
>
If you get the Centris 650 with CD configuration, you are getting a Mac with
a 68RC040 processor that has built-in math coprocessor support.  My 
understanding is that the "optional fpu" refers to your option of purchasing
the Centris 650 4/80 without FPU OR one of the other configurations WITH FPU.

Apple does not offer an upgrade from the non-FPU system to become an FPU
system.  And, it is unclear whether the '040 processor on the non-FPU system
(a 68LC040) can be replaced with a 68RC040 supplied by another vendor.
Apple did send a memo out at one point sating that the Centris 610, which ONLY
comes with a non-FPU 68LC040 processor CANNOT be upgraded to support an FPU -
the pin configurations of the two chips apparently do not match so you cannot
swap one for another (again, according to Apple's memo).

Hope that helps.

Kevin Lohman
University Book Store, University of Washington
Buyer for the UW Apple Computers for Education Program
