From: dmm@cfa.harvard.edu (David Meleedy)
Newsgroups: comp.sys.mac.hardware,comp.sys.mac.misc
Subject: Re: The LCII FUBAR
Date: 13 Apr 92 18:39:59 GMT
Reply-To: meleedy@cfa.harvard.edu
Distribution: na
Organization: Smithsonian Astrophysical Observatory, Cambridge, MA,  USA

according to the article "An Updated LC and LaserWriter Duo" in MacWorld
May 1992:

" The main difference: Apple replaced the LC's aging Motorola 68020 processor
  with a 68030--the same chip that drives most other Macs.  But to keep
  costs down and bring the LC II to market quickly, Apple elected not to
  improve the rest of the LC II's hardware to take advantage of its new
  processor.  As a result, the LC II is no faster than the LC.  The only
  benefit of the LC II's 68030 is that it allows the machine to support
  System 7's virtual memory feature.

 ...

  The LC II's 68030 runs at the same 16MHz clock speed as the LC's 68020
  (and the 030 in the Classic II).  By keeping the clock speed the same,
  Apple has ensured that users won't encounter software incompatibilities.
  Performance, however will not improve.  Although the 68030 is a 32-bit
  processor, the LC II moves data between the processor and memory in 16-bit
  chunks--as did the original LC.  This is why the LC II is no faster than
  its predecessor.  Apple says 32-bit data pathways would have boosted
  performance by up to 30 percent, but would have required a time-consuming
  and costly logic board redesign.

...

  One noteworthy change is the absence of a connector for a second floppy
  disk drive.  Unlike the LC, the LC II can accomodate only one floppy drive.

...

  The original LC included 2 MB of memory and had two SIMM slots to accomodate
  expansion to a total of 10MB.  THe LC II includes 4MB of memory but
  unfortunately still can't accomodate more than 10MB.  To reach 10MB, you
  must supplement the built-in 4MB by installing 8MB in the form of two
  4MB SIMMs.  But doesn't 4MB plus 8MB equal 12MB?  Not to an LC II.  Its
  memory-controller chip can't recognize more than 10MB, so the extra 2MB
  are wasted.  Fixing this would have required a new memory-controller chip,
  and that would have delayed the release of the machine and raised its cost--
  score another for economics over innovation.  The LC II's product manager
  said it's unlikely any third-party products would let the machine recognize
  the wasted 2MB.

...

  The LC II retains the same single expansion slot found in its predecessor,
  although because the LC II doesn't use the 68020 processor, the slot is no
  longer called the 020 Direct Slot.  Its new moniker is the LC Slot, and
  Apple says it will be the standard expansion slot design for its low-end,
  high-volume computers.  Supposedly the slot's name is all that has changed.
  Apple claims most boards designed for the original LC will work without
  modification in the LC II.  Still, some boards--including Apple's own
  Ethernet LC Card and Apple IIe Card-- will require updated ROM chips or
  driver software.

...

  Apple modified the LC II's built-in video circuitry slightly to provide a
  video signal that is more compatible with the low-cost, multisync monitors
  that have been so popular for DOS PCs and that are now being sold for the Mac.
-- 
=======
David Meleedy				Smithonian Astrophysical Observatory
meleedy@cfa.harvard.edu			60 Garden Street, MS 70
Phone: 617 495 7252			Cambridge, MA  02138  USA
Newsgroups: comp.sys.mac.hardware