Re: Upgrading a Rom 0 gs

[dempson@atlantis.actrix.gen.nz (David Empson)]

In article <bongini.94.2F1DA9D7@law3.law.ucla.edu>,
STEPHEN BONGINI <bongini@law3.law.ucla.edu> wrote:
> 
> I need to upgrade a Rom 0 //gs I just bought.  Do I have to just call around 
> to Apple dealers to see who has one laying around?

Rather unlikely.

> Or, can the dealer still order the upgrade from Apple?

I would expect that you can still get this upgrade from Apple, through
a dealer.

There are potentially two parts to the upgrade.  You definitely need
the version 1 ROM, which is a single chip swap.

You might also need a replacement Video Graphics Controller (VGC),
which is a socketed PLCC chip that provides the IIgs video modes.  The
original VGC had a design fault, that caused weird flickering and pink
fringing effects in double hi-res graphics mode (especially monochrome
double hi-res), and also in 80-column text mode in some cases.

If you have the original IIgs system software (System 2.0 or earlier)
and an RGB monitor, boot it and see if the desktop display is an even
grey colour.  If there is any flickering or pink areas, you need an
upgraded VGC as well.


If you are unsuccessful in getting these chips from Apple (it should
be a free upgrade), you can buy them from Alltech Electronics.  The
VGC is not simple to replace - you need a special tool to remove the
old chip, and I wouldn't recommend doing this yourself, unless you
haven't experience with socketed PLCC chips.
-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand