Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!samsung!brutus.cs.uiuc.edu!rpi!leah!albanycs!crdgw1!crdos1!davidsen
From: davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr)
Newsgroups: comp.sys.ibm.pc
Subject: Re: VGA and disk questions
Keywords: VGA, disk, unix, pc
Message-ID: <1880@crdos1.crd.ge.COM>
Date: 6 Dec 89 21:35:21 GMT
References: <667@eedsp.eedsp.gatech.edu>
Distribution: usa
Organization: GE Corp R&D Center, Schenectady NY
Lines: 65
Reply-exos:@crdgw1:To: davidsen@crdos1.crd.ge.com (bill davidsen)

In article <667@eedsp.eedsp.gatech.edu> smg@eedsp.gatech.edu (Stephen McGrath) writes:

| I am thinking of investing in a 386 machine, probably 25 MHz. I would like
| to draw on the experience of people who have been running dos and/or unix
| on such systems to try and evaluate how valuable some options may be. 

  I've been running a 386 for three years at Christmas, and several at
work. I did run DOS with Desqview for about six months until I could get
a 386 version of UNIX.

| First, I would like to know whether there is any benefit to a 1024x768 VGA
| display over, say, an 800x600 VGA display system. Are there many applications
| under dos that will use the 1024x768 mode? Is the 1024x768 VGA display
| supported under unix? 

  There are some DOS programs which use this now, but the only thing in
UNIX which commonly uses high-res graphics is X-windows. It adds little
to the cost of the card, but a good bit to the cost of the monitor. You
have to decide what you current and future needs are.

| Secondly, the disk issue. I am trying to decide whether to get an ESDI
| interface drive or a standard interface RLL drive. I am aware of the difference
| in the speeds of the two types of interface, but I would like to know what 
| is and is not supported under 
| current flavors of unix. 

  The Western Digital RLL and ESDI controllers look like MFM versions
and will work with most versions of UNIX. I'm running Xenix on one RLL
and one ESDI with these controllers. If you go RLL the part is
WD1006VSR2. The V means track buffered in hardware instead of the BIOS,
and up to 3:1 faster on some versions of UNIX. The ESDI is WD1007xxxx (I
don't have the part number handy). If you use an RLL, ESDI, or SCSI
controller which doesn't look like MFM you will probably need a
different version of UNIX, but it's available.

  There is no significant difference in performance between the RLL and
ESDI controller *if you have the track buffering*. Beware of controllers
which claim track buffering but do it in the BIOS... you lose
performance with most version of UNIX.

  You want 4MB or more RAM, and absolute minimum 40MB disk for UNIX. If
you want a DOS partition add that to the UNIX. With all the stuff on the
net you may want to run, you probably will want even more than that (at
home I run 144MB on the "personal" drive, and 62MB for the "public
access" (BBS & news) portion. That includes the archive server at
sixhub, which will be getting another 100MB or so next year after I add
memory and modems.

  Note that you can run two disk controllers with Xenix and some SysV
versions, and many hard drives and tape drives on SCSI. When you use
small drives, <150MB, the RLL are usually cheaper, particularly if you
run an MFM drive as RLL. For larger sizes the ESDI and SCSI get cheaper.

  What I'm saying is that you should look where you want to be over the
life of the machine, like 3-6 years, and if you are going to want "big"
then, go with ESDI or SCSI now. If you go with a large disk think HARD
about a tape drive. The 60s are good because they are big enough to be
useful, and there is a standard format. You can run the same tape on
Xenix, SysV, SunOS, etc, and share data and source even if the
executables won't run.
-- 
bill davidsen	(davidsen@crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen)
"The world is filled with fools. They blindly follow their so-called
'reason' in the face of the church and common sense. Any fool can see
that the world is flat!" - anon