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Re: Video "upgrade" chip
- Subject: Re: Video "upgrade" chip
- From: dempson@actrix.gen.nz (David Empson)
- Date: Sat, 17 Jul 2010 18:21:51 +1200
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golfrock <rtspitz@gmail.com> wrote:
> I keep seeing these on eBay, #370323426845. 344S0046-C Video Graphics
> Chip. In my IIGS there is a 46-2 VGC.
>
> What would be the reason to put this -C one in?
If you have the original ROM 00 IIgs, generally the ones with the "Woz"
signature stamped on the case, the original VGC (revision 0) had a
design flaw: in monochrome double hi-res graphics mode, and for some
combinations of foreground and background colour in 80-column text mode,
white pixels were displayed as pink and may flicker.
My original IIgs was affected by this problem. The solution was an
official Apple upgrade to revision C of the VGC, which was part of a
free upgrade kit along with ROM 01 (which had to be installed by an
Apple dealer).
All logic boards with the faulty VGC have it in an socket. Later models
(e.g. ROM 3) may have the VGC soldered onto the logic board, but I
haven't had a close look to confirm that.
--
David Empson
dempson@actrix.gen.nz