Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!wuarchive!gem.mps.ohio-state.edu!ginosko!uunet!zephyr.ens.tek.com!tekcrl!tekgvs!keithe
From: keithe@tekgvs.LABS.TEK.COM (Keith Ericson)
Newsgroups: comp.unix.i386
Subject: Re: How to choose a new 386 UNIX PC...
Message-ID: <5962@tekgvs.LABS.TEK.COM>
Date: 19 Sep 89 20:37:35 GMT
References: <641@visdc.UUCP> <16081@vail.ICO.ISC.COM>
Reply-To: keithe@tekgvs.LABS.TEK.COM (Keith Ericson)
Organization: Tektronix, Inc., Beaverton,  OR.
Lines: 24

In article <16081@vail.ICO.ISC.COM> scottw@ico.ISC.COM (Scott Wiesner) writes:
>
>8 bit vs. 16 bit really nets you nothing for most graphics operations
>on a VGA board.  This is mostly marketing hype.  They're getting faster
>text mode operation (where you write an attribute and data byte pair), 
>but the EGA and VGA are 8 bit devices internally.

Except that a (properly done) 16 bit card can yank on the 0WS (meaning
"don't add any additional wait states") which an 8-bit card cannot.
An 8-bit card gets a minimum (as I recall) of 3 wait states (and it
might be 5 or 7, I can't recall and the local expert isn't in right
now for me to ask) whereas the 16-bit cards can eliminate most (not
all) of the I/O bus wait states.  The display system may not be a
whole lot faster, but maybe the machine can get on to something else
a bit sooner.

By the way, we're currently using a Tatung VGA as standard equipment
around here.  It's the one that has (1) the Video7 IC's and (2) only
to 256k (maximum) display RAM.  (It turns out the 256k limit isn't
important for our purposes.)  Tatung makes another 16-bit VGA that
uses the Paradise chipset which is an inferior-performing card, so be
sure you get the Video7 clone if you're evaluating or buying.

kEITHe