ASUS TX97-E

  • Thread starter Thread starter Mike
  • Start date Start date
M

Mike

Hi,

I still use a TX97-E with a K6-III+ @ 500 MHz as my Linux server. I am
building a RAID system of 5x 9G SCSI drives inside the case, and therefore I
need a heavier powersupply.

The question I have is about the powersupply.

The mobo is now fed by an older AT power supply, which only gives 12 and 5
volt. (9 and 22 A)

The mobo can take an ATX powersupply too, but the difference is that an ATX
powersupply also delivers 3.3 volt.

Does anyone know if the TX97-E benefits from the extra 3.3 volt rail from
the ATX supply, or does the TX97-e only connects to the 12 and 5 volt rail?


Thanks in advance,


Mike.
 
Hi,

I still use a TX97-E with a K6-III+ @ 500 MHz as my Linux server. I am
building a RAID system of 5x 9G SCSI drives inside the case, and therefore I
need a heavier powersupply.

The question I have is about the powersupply.

The mobo is now fed by an older AT power supply, which only gives 12 and 5
volt. (9 and 22 A)

The mobo can take an ATX powersupply too, but the difference is that an ATX
powersupply also delivers 3.3 volt.

Does anyone know if the TX97-E benefits from the extra 3.3 volt rail from
the ATX supply, or does the TX97-e only connects to the 12 and 5 volt rail?


Thanks in advance,


Mike.
Click to expand...

Interesting. According to the manual, your motherboard has both AT
and ATX power connectors. The ATX power connector has 3.3V signals
on it, while the AT is missing those. That means when using the
ATX, there will be no load on the +3.3V.

If anything, I would be careful that your new power supply still
has the -5V on it. I don't know if there is any technology on your
board that uses it, but it is always remotely possible that it
does need it. The ATX 2.01 or 2.03 version power supplies might
have -5V listed as optional. I think someone lately had a Enermax
that was missing -5V.

As for whether the (unloaded) 3.3V feed is going to be a problem,
I would want a supply that lists 0 amps minimum load on the 3.3V
rail.

Again, just picking on Enermax for a moment, the supplies here
list a 0.5 amp minimum load on 3.3V. (While it probably doesn't
matter, since the 3.3V is not actually being used, usually the
3.3V rail has a feedback wire on one of the 3.3V pins, and if the
3.3V is going to go out of spec, it might actually move the other
rails around a bit.) As these are 2.01 version supplies, there is
no -5V rail.

http://www.enermax.com.tw/products_page.php?Tid=1&gon=264&Gid=18&Gid2=46

This one has a zero amp minimum load on 3.3V.

http://www.antec.com/specs/true380_spe.html

So, those are the only (weak) criteria I can think of for your
purchase. At the very least, purchase a power supply where the
manufacturer lists specs. Some of the cheapest supplies don't
even bother with specs on the manufacturer's web site - that is
a definite bad sign. If it is being sold based on the blue LED
that lights up the case, or on the UV reactive wire insulation,
you know how long a supply like that is going to last...

Paul
 
Paul said:
Interesting. According to the manual, your motherboard has both AT
and ATX power connectors. The ATX power connector has 3.3V signals
on it, while the AT is missing those. That means when using the
ATX, there will be no load on the +3.3V.
Click to expand...

Hi Paul,

Thank you very much for your answer and your clear advise about the PS!

I asked somewhere else the same question, and someone said that if available
it uses the 3.3 volt rail from the ATX PS to power the memory. If not, this
power is derived from the 5 volt rail.

Hmm, now I'm doubting again.

Do you know resources or official tech docs which describes this issue?

Thanks,


Mike.
 
"Alice in Chains" said:
Hi Paul,

Thank you very much for your answer and your clear advise about the PS!

I asked somewhere else the same question, and someone said that if available
it uses the 3.3 volt rail from the ATX PS to power the memory. If not, this
power is derived from the 5 volt rail.

Hmm, now I'm doubting again.

Do you know resources or official tech docs which describes this issue?

Thanks,


Mike.
Click to expand...

That seems like an excessively complicated implementation.

If the board can be run from an AT supply, then it must have
a solution to make the necessary +3.3V from +5V, for use
with the +3.3V memories. The simplest implementation (and
Asus likes simple), would be to just not use +3.3V. To diode
OR the +5V and +3.3V, and then make +3.3V from it, would likely
require a boost/buck converter, and that is expensive and
pointless in this application. I don't see any selection
jumpers, as evidence of such jumpers would support the
other poster's theory. (In other words, if such an option
were to exist, it would profit greatly from the use of
jumpers - the user would jumper the +3.3V supply to the
ATX supply, when an ATX supply was being used. If no
jumpers of that type are present, then an automated selector
would cost too much to include on the board.)

I cannot find a high resolution picture of the motherboard,
so it isn't possible to guess at what is being done on the
board, based on pictures. Otherwise I'd look for any power
conversion devices (and the devices should be located near
the load, to make the signal routing easier). I see a black
square near the power connectors, but cannot even make out
how many pins it has on it.

If you look in Google, there seem to be lots of people
using AT or ATX supplies with the board, and I take that as
a positive sign.

In terms of FAQs, you can look here, but I don't see any
mention of powering:

http://www.asuscom.de/support/contact/mainboard/s7_intel_tx.htm

Paul
 
Back
Top