Re: Uprgading IIgs

[spec@vax2.concordia.ca (Mitchell Spector)]

In article "Jay C. Sabol" <jaycs@earthlink.net> writes...

>I have the impression that having ROM 01 does not prevent me from
>attaching a hard drive, using GS/OS 6.01, upgrading RAM, attaching a
>modem, etc.

    That is correct, the original motherboard with the ROM 01 revision
does not have any limitations that prevent you from doing upgrades or
using the latest software.

>I am still a little unclear about what I am losing by not having those
>extra intsructions in the ROM 03. Would the difference be enough so as
>to be worthwhile to get ROM 03 motherboard and replace my current
>motherboard?

    What you lose in minimal. The ROM 3 (incidentally, there is no such
thing as a "ROM 03") has eight times the amount of Fast RAM built-in,
so out of the box you start off with 1152K, versus only 256K on the 01.
In either case you'll want to add more memory, but since there is that
extra 1 MB on the motherboard, you can have up to 5 MB of DMA memory
rather than just 4 MB.

    By "extra instructions" I assume your referring to the additional
features in ROM firmware. That has an advantage too, a number of tools
from System 5 are present in ROM which will not have to be loaded when
you launch GS/OS. This has the benefit of a slightly faster boot time
and slight speed increase in redrawing menus, windows and scrolling
(due to the fact tools are read from ROM instead of RAM, and ROM is
accessed at a full 2.8 MHz. Tools in RAM access at 2.5 to 2.6 MHz,
because they're subject to refresh cycles).

    Further enhancements in firmware give you more flexibility when
working with AppleTalk (no longer are you forced to give up slot 7),
your 3.5 drive and RAM Disk operate a bit faster in 8-bit mode and 
you have an improved Control Panel with more options.

    In terms of hardware, the biggest advantage you'll notice is there
is less interference and electrical noise produced by the motherboard.
This means less buzzing/hissing from the Ensoniq sound chip, and a
greater chance sensitive boards like high-speed accelerators will work
(I'm running a 15 MHz accelerator on my ROM 3, but I doubt I could get
it working more than 10-12 MHz on my ROM 01 or be stable).

    You also have the newer ADB keyboard micro, which gives you features
like sticky keys and mouse keyboard built-in, as well as the 'Caps Lock'
LED working if you every decide to add an extended keyboard. Another nice
thing is the clock/Control Panel battery is removable should it ever need
to be replaced.

>Thank you very much in advance for any advice/suggestions/opinions on
>this matter!

    Well my advice is don't rush out and trade your ROM 01 board for
a ROM 3, unless any of the above features (I've listed only the major
ones) appeal to you. I only consider the ROM 3 significant to long
time users of the Apple IIgs, anyone who's used a different platform
will not consider any of it's enhancements significant enough to take
notice. All things considered, it still very much looks and acts like
the original Apple IIgs released in 1986 (thanks to Apple doing its
best to sit on the design and keeping its appeal below that of the
Macintosh).

    Some will point out that the ROM 3 is not compatible with certain
software, but that mostly just includes a small handful of old games
and demos (and I can personally tell you anything that was worth
booting up was patched long ago ;). Apple used to point out that a
number of benefits with the ROM 3 could be obtained on the ROM 01
by using the (then) latest System Software 5.0.2 and adding a 1 MB
expansion board.

Mitchell Spector
spec@vax2.concordia.ca