[comp.sys.ibm.pc.misc] DTK Motherboards

jsavage@van-bc.wimsey.bc.ca (Julian Savage) (11/18/90)

I am considering buying a DTK brand motherboard, mainly because the price is  
right, but I would like to find out from anyone with first-hand experience
just how reliable they are, and also what brand the relevant chips on the 286@16
and 386@16 boards are. Please either Email me or post to this newsgroup. 
 

thanks

-=-
Julian Savage
 
jsavage@van-bc.wimsey.bc.ca  or  ..!van-bc!jsavage

jca@pnet01.cts.com (John C. Archambeau) (11/19/90)

jsavage@van-bc.wimsey.bc.ca (Julian Savage) writes:
>I am considering buying a DTK brand motherboard, mainly because the price is  
>right, but I would like to find out from anyone with first-hand experience
>just how reliable they are, and also what brand the relevant chips on the 286@16
>and 386@16 boards are. Please either Email me or post to this newsgroup. 

I would not buy a DTK motherboard because of the problems documented in going
in and out of protected mode on the 386.  Their 286 boards aren't that great
because some of the later versions only support expanded memory.  Makes things
really nice if you want to run MicroPort Unix or SCO Xenix 286.

The problem with DTK's 386 motherboards is so well documented that Novell has
an official patch to make Netware run on a DTK 386 motherboard.  Not good, if
Novell acknowledges that there's a problem, then there's a series problem!

Look into another manufacturer of motherboard please!  You'll thank yourself
later.
 
     // JCA

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hoepfner@usun01.UUCP (Andreas Hoepfner) (11/20/90)

In <5714@crash.cts.com> jca@pnet01.cts.com (John C. Archambeau) writes:


>I would not buy a DTK motherboard because of the problems documented in going
>in and out of protected mode on the 386.  Their 286 boards aren't that great
>because some of the later versions only support expanded memory.  Makes things
>really nice if you want to run MicroPort Unix or SCO Xenix 286.

 Shure, but it is possible to fix the problem by changing the keybord-
 controller *AND* the BIOS from DTK to PHOENIX !
 I've just done this and the board works fine......

 Andreas


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fcr@saturn.wustl.edu (Frank C. Robey ) (11/21/90)

In article <5714@crash.cts.com> jca@pnet01.cts.com (John C. Archambeau) writes:
>jsavage@van-bc.wimsey.bc.ca (Julian Savage) writes:
>>I am considering buying a DTK brand motherboard, mainly because the price is
>>right, but I would like to find out from anyone with first-hand experience
>>just how reliable they are, and also what brand the relevant chips on the 286@16
>>and 386@16 boards are.
>
>I would not buy a DTK motherboard because of the problems documented in going
>in and out of protected mode on the 386.  
>

I have had a DTK motherboard for almost a year now and I have been very
happy with it.  I use windows 3.0 and a memory manager that use protected
mode and have not had any problem with going in or out of protected mode.
Since DTK make 5 or 6 386 motherboards are there certain ones which have a
problem?  I did not do anything special for installation.  

I have the 386-25MHz PEMM board with 64k cache memory and it has run
everything that I have tried to run on it.

Just a satisfied customer.

Frank Robey
fcr@saturn.wustl.edu	fcr@wuee1.wustl.edu
Electronic Systems and Signals Research Laboratory
Washington University- St. Louis

fac7@dayton.saic.com (Steven Poling) (11/22/90)

In article <1990Nov20.180552.3474@cec1.wustl.edu>, fcr@saturn.wustl.edu (Frank C. Robey ) writes:
> In article <5714@crash.cts.com> jca@pnet01.cts.com (John C. Archambeau) writes:
>>jsavage@van-bc.wimsey.bc.ca (Julian Savage) writes:
>>>I am considering buying a DTK brand motherboard, mainly because the price is
>>>right, but I would like to find out from anyone with first-hand experience
>>>just how reliable they are, and also what brand the relevant chips on the 286@16
>>>and 386@16 boards are.
>>
>>I would not buy a DTK motherboard because of the problems documented in going
>>in and out of protected mode on the 386.  
>>
> 
I have had experience with DTK motherboards for the past 4 years now and have
had some problems with some of their 286 boards during the first part of 1989
but after that I have sold many DTK motherboards and know of one business
here in Dayton that will sell only DTK motherboards.  Just remember, if you
are going to buy a clone motherboard..... know the people that you are buying
it from or buy it from someone else who knows the company/people.  Steve


-- 
_____________________________________________________________________________
               ____ ____    ___
Steven Poling /___ /___/ / /   Science Applications International Corporation
             ____//   / / /__                 Dayton, Ohio
-----------------------------------------------------------------------------
Internet: poling@dayton.saic.com     

jdb@beach.cis.ufl.edu (Brian W.K. Hook) (11/22/90)

I have worked on and used a plethora of DTK boards, and to be honest, I don't
like them.  The DTK BIOS is not too wonderful (as a matter of fact, the last
time I checked it couldn't run OS/2).  The board has had bus-timing problems
and synchronization problems with some video cards, and it has a hard time
with certain hard drives getting up to speed (specifically the DTK 286-16 
and ST277R 65MB RLL Seagate).

On another note, here in Gainesville (a rather small town) there are FIVE
DTK dealers.  DTK used to be pretty big back in the mid-Eighties, but have
since lost their technical edge.  Thus they are trying to undercut and
sell quantity at low prices.  Quality control has DEFINITELY suffered.
And the reason I mentioend that FIVE dealers are in town shows that DTK
does not really deal with big manufacturers.  They sell all their equipment
at dirt prices to distributors, who in turn indiscriminately sell to retailers
that are going simply for bottom dollar.

As far as replacement motherboards, price and performancer wise Jameco and
JDR Microdevices are supposed to have rather nice boards.  But the best in
the industry have got to be either Micronics or Mylex.

ssingh@watserv1.waterloo.edu (The Sanj - ISman (iceman)) (12/05/90)

I have a question on DTK 386sx boards. I have a PPM 1630. I bought it 
in August of last year. I asked for 80 nanosecond RAMs. The board
is supposed to take 120 nanosecond RAMs. I was hoping for zero-wait-states.

When I saw that the Landmark rating was only 16 Mhz (not 18 or so), I started
asking questions.

I was told that the motherboard couldn't handle it.

Then I was told that I could get zero-wait-states by changing to the
latest BIOS. Supposedly DTK has only changed the BIOS to allow for
zero-wait-states.

Which brings me to the next question. I looked in Que's "Computer User's
Dictionary" (highly recommended) for the definition of wait state. It
said that these were "programmed into the system" to allow slower memory
to keep up with the CPU.

Presumably this means programmed into the BIOS. But it wouldn't work to
simply insert NOP (do nothing) instructions in the BIOS because the CPU
would be trying to execute the NOP instrutions themselves without any
slowdown. Finally, I came to the conjecture that since I have heard of
the idea of ROM shadowing on video cards to copy video BIOS into RAM for
faster execution, probably how wait states are implemented is that
using ROM chips causes enough of a slowdown to prevent timing problems.
This would cohere well with the idea of BIOS-shadowing offered by many
vendors of PC-compatibles.

First, is my reasoning correct?

Second, would using the latest version of DTK BIOS on a PPM 1630 with
80 nanosecond RAMS increase throughput? Does the latest version of
DTK BIOS allow BIOS shadowing? Does anyone have benchmarks available?

Lastly, what about operating systems like UNIX that bypass the BIOS
entirely, since all operations would be done in RAM, does this mean that
running UNIX would automatically yield better performance? If so, what
about timing problems, if I had used 120 ns. RAMs?

I know this is a barrage of questions, but I need help in this rather
important decision, and opinions, as you know are often contradictory.

Any assistance would be appreciated.

Ice.

-- 
"Weapon systems are L[+]CKED on you, Johnny-cake..."  
$anjay $ingh     Provost-Hunter     ssingh@watserv1.[u]waterloo.{edu|cdn}/[ca]
jwwong@a-provost: "I Come In Peace."	ssingh@watserv1: "You Go In Pieces."
"If this alt stuff makes you feel like shit, go to the john."-ssingh@watserv1

daly@ecs.umass.edu (Bryon Daly, ECE dept, UMass, Amherst) (12/06/90)

In article <1990Dec5.015847.21620@watserv1.waterloo.edu>, ssingh@watserv1.waterloo.edu (The Sanj - ISman (iceman)) writes:
> I have a question on DTK 386sx boards. I have a PPM 1630. I bought it 
> in August of last year. I asked for 80 nanosecond RAMs. The board
> is supposed to take 120 nanosecond RAMs. I was hoping for zero-wait-states.

Sadly, I don't think 80ns DRAMs could give you zero wait states, anyway.
If your 386SX is running at 16MHz, that means 16 million cycles per second,
or 62.5 ns per cycle.  If the machine is capable of generating an access to
memory every clock cycle --- (I imagine that a NOP only takes one cycle, so
a series of NOP's would generate a series of reads to memory for the next
instruction, one read per clock [Note this ignores such concerns a pipelining
and word size]) --- then it would want to read memory once every 62.5 ns.
If the DRAM speed rating is 80 ns, they could not keep up with this peek
access rate.  If the CPU tries to access memory, but the RAM is not fast
enough to respond before the end of the cycle, a wait state must be added
(maybe more than one if the CPU is fast enough and the RAM slow enough.) to
the CPU cycles to give the memory a chance to catch up.  Note that the wait
states are not in the form of an executed instruction such as a NOP; they
occur at the deeper, hardware level.  On the Intel microprocessor I worked
with (8085), there was a wait line on the chip itself ( I think the 8086 is 
the same).  If, after the CPU tries to access memory, the wait line is asserted
(presumably by the motherboard memory logic), the CPU will just sit and idle 
away clock cycles (ie; wait) until the wait line is unasserted, (and thus the 
data is ready for the CPU to read.)  Note also, I don't think that the DRAMS
themselves have any capability of saying that they need more time; too slow
DRAMS in a motherboard expecting faster ones will probably just not function
correctly.  Thus it is up to the motherboard to decide when wait states are
needed.  The motherboard of my 12MHz 286 has a jumper on it which decides
how many wait states the CPU will run at.  I once placed the jumper in the
wrong setting and saw my Norton SI drop from 13.7 to 11.9 or so.

> 
> When I saw that the Landmark rating was only 16 Mhz (not 18 or so), I started
> asking questions.
> 
> I was told that the motherboard couldn't handle it.
> 
> Then I was told that I could get zero-wait-states by changing to the
> latest BIOS. Supposedly DTK has only changed the BIOS to allow for
> zero-wait-states.

I've never heard of BIOS deciding on a system's wait states; but that may be
the newest thing.  Still, check your motherboard for undocumented jumpers
(or even documented ones: did you check out the system's manual (for the
motherboard) completely?  Another thought: talk to DTK themselves, instead of
the people you got your system from - they won't know as much about the
motherboard (and wait states) as DTK itself would. 
> 
> Which brings me to the next question. I looked in Que's "Computer User's
> Dictionary" (highly recommended) for the definition of wait state. It
> said that these were "programmed into the system" to allow slower memory
> to keep up with the CPU.

"wired into the system" would probably be a better term

> 
> Presumably this means programmed into the BIOS. But it wouldn't work to
> simply insert NOP (do nothing) instructions in the BIOS because the CPU
> would be trying to execute the NOP instrutions themselves without any
> slowdown. Finally, I came to the conjecture that since I have heard of
> the idea of ROM shadowing on video cards to copy video BIOS into RAM for
> faster execution, probably how wait states are implemented is that
> using ROM chips causes enough of a slowdown to prevent timing problems.
> This would cohere well with the idea of BIOS-shadowing offered by many
> vendors of PC-compatibles.

ROMS are just plain ol' slower than RAMS (for reasons I have yet to discover)
The benefit they offer is permanent storage for the BIOS routines (we wouldn't
want to load them off a floppy, would we?, especially when the boot up sequence
that reads the disk initially is stored in ROM.)  The BIOS routines are
sometimes copied into RAM, which is faster, to increase the performance of the
system.

> 
> First, is my reasoning correct?
> 
> Second, would using the latest version of DTK BIOS on a PPM 1630 with
> 80 nanosecond RAMS increase throughput? Does the latest version of
> DTK BIOS allow BIOS shadowing? Does anyone have benchmarks available?
> 
> Lastly, what about operating systems like UNIX that bypass the BIOS
> entirely, since all operations would be done in RAM, does this mean that
> running UNIX would automatically yield better performance? If so, what
> about timing problems, if I had used 120 ns. RAMs?

Programs not using the BIOS might run faster (since they don't rely on the
slow ROM BIOS routines), but actually now, many programs avoid using the BIOS
as a matter of course.  I.e.: the Turbo C routines for displaying text and
graphics default to NOT using the BIOS (in other words, they use direct access
to the hardware to perform tasks).

> 
> I know this is a barrage of questions, but I need help in this rather
> important decision, and opinions, as you know are often contradictory.
> 
> Any assistance would be appreciated.
> 
> Ice.
> 
                                                                 
Well, I've said my piece.  If any hardware guru's out there notice any flaring
dicrepencies (or outright untruths) please do correct me.

Good Luck,
Bryon Daly, ECE grad student at-large
daly@ecs.umass.edu
---
DISCLAIMER: I tried to speak for my employers, but they told me to shut up!