[comp.sys.ibm.pc] VGA and Disk Questions

smg@eedsp.gatech.edu (Stephen McGrath) (12/05/89)

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
will be running dos for the immediate future, but I want to be able to
run unix (of some as-yet-unspecified flavor) on the system without any
hardware changes.

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? 

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. I remember reading postings recently which seemed
to say standard AT-interface (ST506/418 (?)) RLL drives are not supported
under current versions of 386 unix systems, but that an ESDI or SCSI
interface is required. Is there any truth to this?
I would imagine that 60-120 Meg RLL drives are so common that most
flavors of unix would support them.

I would appreciate any information on these topics from those who have 
experience with these issues. I read this group regularly, so if you wish 
to post your answers I will see them; I think they would be of general
interest. 

Thanks for your time,
-Stephen

Stephen McGrath
Georgia Tech, School of EE, DSP Lab, Atlanta, GA  30332
(404)894-3872
smg@eedsp.gatech.edu

phil@diablo.amd.com (Phil Ngai) (12/06/89)

In article <662@eedsp.eedsp.gatech.edu> smg@eedsp.gatech.edu (Stephen McGrath) writes:
|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? 

I don't know about Unix but your display will typically come with at
least a Windows driver. I also just got 1024x768 support in a
schematic capture program (Orcad) and it makes the difference between
panning and not panning an A size page. 

--
Phil Ngai, phil@diablo.amd.com		{uunet,decwrl,ucbvax}!amdcad!phil
AT&T Unix System V.4: Berkeley Unix for 386 PCs!

smg@eedsp.eedsp.gatech.edu (Stephen McGrath) (12/07/89)

From eedsp!eedsp.gatech.edu!smg Tue Dec  5 16:13:37 EST 1989


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
will be running dos for the immediate future, but I want to be able to
run unix (of some as-yet-unspecified flavor) on the system without any
hardware changes.

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? 

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. I remember reading postings recently which seemed
to say standard AT-interface (ST506/418 (?)) RLL drives are not supported
under current versions of 386 unix systems, but that an ESDI or SCSI
interface is required. Is there any truth to this?
I would imagine that 60-120 Meg RLL drives are so common that most
flavors of unix would support them.

I would appreciate any information on these topics from those who have 
experience with these issues. I read this group regularly, so if you wish 
to post your answers I will see them; I think they would be of general
interest. 

Thanks for your time,
-Stephen


-- 
Stephen McGrath                        School of Electrical Engineering,
smg@eedsp.gatech.edu                   Georgia Tech, Atlanta, GA 30332

davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr) (12/07/89)

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

keithe@tekgvs.LABS.TEK.COM (Keith Ericson) (12/08/89)

In article <662@eedsp.eedsp.gatech.edu> smg@eedsp.gatech.edu (Stephen McGrath) writes:
>...the disk issue. I am trying to decide whether to get an ESDI
>interface drive or a standard interface RLL drive.

>I remember reading postings recently which seemed
>to say standard AT-interface (ST506/418 (?)) RLL drives are not supported
>under current versions of 386 unix systems, but that an ESDI or SCSI
>interface is required. Is there any truth to this?

In the various UNIXes I've installed (AT&T (via INTEL); Interactive; and
INTEL) they've all installed on MFM, RLL and ESDI drives as if it didn't
make a hill of beans of difference.  SCSI is another matter.  I thinks the
RLL and ESDI systems work because the controllers are register-compatible
with the MFM controllers, but I'm not sure...

kEITHe