Path: utzoo!attcan!uunet!cpqhou!scotts
From: scotts@cpqhou.UUCP (Scott Shaffer)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Compaq/IBM VGA display compatibility
Summary: Answer (I hope)
Keywords: compaq, VGA, display
Message-ID: <507@cpqhou.UUCP>
Date: 12 Jan 90 06:00:00 GMT
References: <73211@philabs.Philips.Com>
Lines: 43

In article <73211@philabs.Philips.Com>, dab@briar.philips.com (David Bryan;6247;3.25;$0201) writes:
> I have a Compaq 386/33 MHz machine with something called a Compaq Video
> Graphics Monitor, which is definitely some kind of VGA.  The main 
> application program that I run calls for me to specify whether my display
> is an "IBM VGA mode 12 color display" or an "IBM VGA mode 13 color display".
> Is my Compaq display equivalent to either of these IBM types ?  By the way,
> I have asked Compaq but they can't (or won't) say.  Please e-mail replies
> to me if possible.  Thanks.
> 

In its quest for producing the most inovative products, IBM has done a funny
thing in the way of video adaptors in the PS/2.  Yes IBM improved the EGA
standard with VGA, but they just couldn't resist screwing with things a little.
In the high class PS/2s, a full blown VGA was included.  In the cheaper 
models, MCGA was introduced.  A full blown VGA can support ALL video modes
from 0h to 13h.  An MCGA can't.  The COMPAQ VGA is a full blown VGA and
thus supports all standard VGA modes (no 800x600 or anything).

The modes go like this:
  0-6 : old CGA modes (640x200 & 320x200)
  7   : monochrome (720x350)
  8-10: EGA added modes (640x350)
  10-13: VGA added modes (640x480 max)

  VGA added modes
	11 - 640x480 2 color
	12 - 640x480 16 color
	13 - 320x200 256 color

So, in your case, you can select either.  Selecting mode 12 will get you
increased resolution (and great text), but less colors.  Selecting mode 13
will get you great colors, but poorer resolution.

MCGA supports all of the CGA modes, plus the 320x200 256 color mode.

I hope this clears things up.

Scott Shaffer
Compaq Computer Corp.

(* The above opinions are mine, and nobody elses. *)

BTW, who at Compaq wouldn't tell you?  Did you ask Compaq or your dealer?