Connecting a power supply (or supplies!?) to Tyan Thunder HEsl(S2567)

Hello

I have an opportunity to cheaply acquire a Tyan Thunder HEsl (S2567)
motherboard (link: http://www.tyan.com.tw/archive/produ...thunderhe.html).
This is an equivalent of a oldtimer muscle car, especially since I
have got the best tyres (processors - 2 x P3 Coppermines 1000/133) for
it.

But there is one thing (besides its large size) which bothers me. As
you can see on its picture, this board has TWO 20-pin ATX power
connectors (they are located in the upper right corner of the board -
the worst possible position by the way - underneath the 3.5" drive
cage).

=============

The presence of a dual ATX power connection implies that I would need
two ATX power supplies to use this board, but I have never heard of
such a setup (except of proprietary enterprise servers' redundant
powering systems).
Besides that, as far as my electrotechnical knowledge goes, two
switching power supplies would most likely fry each other when
simultaneously powering the same consumer directly without any
intermeddiate load-balancing (or reundant) electrical regulator. The
direct simultaneous power draw would effectively place them in a "69
position" (excuse me for the profanity), and the two PSUs would suck
each other because of small differences between voltages. This
imbalance would eventually lead to the failrue of one, which would
then kill the other.

=============

The strangest thing is that the section for powering in this
motherboard's user manual (ftp://ftp.tyan.com/manuals/m_s2567_101.pdf)
(page 25) does NOT mention these dual ATX connections at all. It
treats the powering issue just like in any ordinary board - "connect
the ATX 20-pin main power connector to the mainboard, and that's it".

==============

So, what is the true deal here? Do I need only one, ordinary classic
ATX 20-pin power supply, or two of them? If I need two of them, what
are the pecularities of that?


Thank you very much for reading this, and much more for writing a
constructive reply.

- Nihad

Nihad Hamzic <nihad.hamzic@gmail.com> wrote in <6414555b-3c37-419f-aba1-8d186935f0f0@s20g2000yqh.googlegroups.com>:
> Hello
>
> I have an opportunity to cheaply acquire a Tyan Thunder HEsl (S2567)
> motherboard (link: http://www.tyan.com.tw/archive/produ...thunderhe.html).
> This is an equivalent of a oldtimer muscle car, especially since I
> have got the best tyres (processors - 2 x P3 Coppermines 1000/133) for
> it.
>
> But there is one thing (besides its large size) which bothers me. As
> you can see on its picture, this board has TWO 20-pin ATX power
> connectors (they are located in the upper right corner of the board -
> the worst possible position by the way - underneath the 3.5" drive
> cage).

So if you don't want it, I'll be happy to take it off your hands.
Just let me know. I've got a Truly Enormous case.

> =============
>
> The presence of a dual ATX power connection implies that I would need
> two ATX power supplies to use this board, but I have never heard of
> such a setup (except of proprietary enterprise servers' redundant
> powering systems).
> Besides that, as far as my electrotechnical knowledge goes, two
> switching power supplies would most likely fry each other when
> simultaneously powering the same consumer directly without any
> intermeddiate load-balancing (or reundant) electrical regulator. The
> direct simultaneous power draw would effectively place them in a "69
> position" (excuse me for the profanity), and the two PSUs would suck
> each other because of small differences between voltages. This
> imbalance would eventually lead to the failrue of one, which would
> then kill the other.

The manual does, on page 6 under "Form Factor", state that the board
has dual ATX 20-pin power connectors.

What leads you to think that Tyan's designers didn't design the board
so that it would be safe to use two supplies? Failure to design the
power-distribution aspects of the board, if in fact they did intend that
two power supplies should be connected, would be an egregious failure
inndeed. But if they didn't so intend, why would they have used precious
board real estate to accommodate the second connector and its wiring?
This isn't an accident, I think, but a feature.

> =============
>
> The strangest thing is that the section for powering in this
> motherboard's user manual (ftp://ftp.tyan.com/manuals/m_s2567_101.pdf)
> (page 25) does NOT mention these dual ATX connections at all. It
> treats the powering issue just like in any ordinary board - "connect
> the ATX 20-pin main power connector to the mainboard, and that's it".
>
> ==============
>
> So, what is the true deal here? Do I need only one, ordinary classic
> ATX 20-pin power supply, or two of them? If I need two of them, what
> are the pecularities of that?
>
>
> Thank you very much for reading this, and much more for writing a
> constructive reply.

Try it with one supply. See if it works, if it tends to have problems
under heavy load. And maybe send E-mail to Tyan Tech Support, or give
them a phone call, first, before you even buy the board, just to see
what they have to say on the subject -- other than "too old, no longer
supported".

Looks like a fine, if slightly towards the vintage side of the calendar,
piece of work. Good luck with it.

--
Mike Andrews, W5EGO
mikea@mikea.ath.cx
Tired old sysadmin