Who makes a decent "AT" motherboard for PIII or P4 ?

[Fred Mau]

I have a really nice industrial rack-mount case that I'd like to do
something with, but it's made for the old standard "AT" form factor.

Can anybody recommend a good reliable recent-vintage motherboard in the AT
form factor ? I don't need the latest and greatest; A P4 would be nice, but
anything from about a PIII-600 on up would be sufficient, I'll be using it
to run text-mode freeBSD or Linux and act as a small non-critical database
server.

TIA.

- FM -

 

[Al Dykes]

I have a really nice industrial rack-mount case that I'd like to do
something with, but it's made for the old standard "AT" form factor.

Can anybody recommend a good reliable recent-vintage motherboard in the AT
form factor ? I don't need the latest and greatest; A P4 would be nice, but
anything from about a PIII-600 on up would be sufficient, I'll be using it
to run text-mode freeBSD or Linux and act as a small non-critical database
server.

TIA.

- FM -

Anything by Supermicro would be great. Ebay is your best bet. I think
you should be looking Xeon or pentium pro boards. Get a couple
spare power supplies while you're at it.

AT was phased out a long time ago, in CPU years.

 

[ric]

Anything by Supermicro would be great. Ebay is your best bet. I think
you should be looking Xeon or pentium pro boards. Get a couple
spare power supplies while you're at it.

ATX power supplies work fine in AT systems, just not the other way
around.

 

[Al Dykes]

ATX power supplies work fine in AT systems, just not the other way
around.

Are there atx PSUs that fit neatly in AT boxes ? ISTR that the AT
power supplies were huge by today's standards.

 

[Wes Newell]

Are there atx PSUs that fit neatly in AT boxes ? ISTR that the AT
power supplies were huge by today's standards.

If you had a mid tower AT PSU, the ATX PSU is the same size, same mount
holes, etc. The size is 5 7/8" x 5 5/8" x 3 5/16" (147x140x82mm) according
to my measurements.

 

[ric]

Are there atx PSUs that fit neatly in AT boxes ? ISTR that the AT
power supplies were huge by today's standards.

There were *many* physical sizes of PSUs that worked with the AT
*electrical* specification. "Slim" size PSUs, quite popular during
the latter stage of the AT era, are identical in size and hole layout
to ATX type PSUs. Many AT cases accepted this size PSU. These cases
will also accept ATX PSUs.

If the case *only* accepts the big 8.35" x 5.9" x 5.9" full tower size
AT PSU, they are still available (Google on "AT power supply".)

 

[JT]

I have a really nice industrial rack-mount case that I'd like to do
something with, but it's made for the old standard "AT" form factor.

Can anybody recommend a good reliable recent-vintage motherboard in the AT
form factor ? I don't need the latest and greatest; A P4 would be nice, but
anything from about a PIII-600 on up would be sufficient, I'll be using it
to run text-mode freeBSD or Linux and act as a small non-critical database
server.

TIA.

- FM -

Best you can find is an OLD P3 motherboard in AT. There has not been an ATX
P4 motherboard. Good luck finding one.

JT

 

[JT]

Best you can find is an OLD P3 motherboard in AT. There has not been an ATX
P4 motherboard. Good luck finding one.

JT

Oops. Coffee level too low. Meant there are no AT P4 motherboards

JT

 

[Gary Tait]

I have a really nice industrial rack-mount case that I'd like to do
something with, but it's made for the old standard "AT" form factor.

Can anybody recommend a good reliable recent-vintage motherboard in the AT
form factor ? I don't need the latest and greatest; A P4 would be nice, but
anything from about a PIII-600 on up would be sufficient, I'll be using it
to run text-mode freeBSD or Linux and act as a small non-critical database
server.

TIA.

- FM -

I'd break out the dremel.

 

[David Maynard]

Al Dykes wrote:




There were *many* physical sizes of PSUs that worked with the AT
*electrical* specification. "Slim" size PSUs, quite popular during
the latter stage of the AT era, are identical in size and hole layout
to ATX type PSUs. Many AT cases accepted this size PSU. These cases
will also accept ATX PSUs.

True, except that they mount in reverse of each other (fan outlet--power
entry reverse rear position), meaning the ATX supply will be 'upside down'
in an AT case. That's not really a problem unless you're counting on the
'second fan' in a dual fan PSU for anything. The power switch has to be
changed too as the AT switch is an AC alternate action/toggle type whereas
the ATX is a momentary action connected to the mobo.

The bigger problem is the motherboard. An ATX won't mount in the same
footprint as an AT because of the rear connector panel (there IS no 'rear
connector area', beyond the keyboard (and occasionally PS2 mouse), on an AT
motherboard. Further, if it's designed 'snug', I.E. PSU butted up to the
motherboard, then you can't dremmel a solution either because the ATX mobo
extends further than the AT mobo in that direction. If there's enough
'slack' between them you can as the hole pattern is the same on the
'ISA/PCI' side and you can hack out a rear panel connector hole in the case
on the other side (I've done it).

 

[ric]

True, except that they mount in reverse of each other (fan outlet--power
entry reverse rear position), meaning the ATX supply will be 'upside down'
in an AT case. That's not really a problem unless you're counting on the
'second fan' in a dual fan PSU for anything.

If, as planned, he is using it to power an AT motherboard, the CPU will
not be directly below the PSU (as it is on an ATX board), so the fan will
be case air circulating only. As such, the top location may even be better.

The power switch has to be
changed too as the AT switch is an AC alternate action/toggle type whereas
the ATX is a momentary action connected to the mobo.

Again, he is trying to power an AT motherboard with an ATX PSU. The ON/OFF
problem is addressed in the PSU/MB connector adapter. See:

http://www.pcpowercooling.com/products/cooling/accessories/popups/indexatxtoatcable.htm

The bigger problem is the motherboard.

But since we're discussing the PSU, this is irrelevant. [Besides, he
planned on putting an AT motherboard in an AT case.] Read the OP.

 

[David Maynard]

David Maynard wrote:




If, as planned, he is using it to power an AT motherboard, the CPU will
not be directly below the PSU (as it is on an ATX board), so the fan will
be case air circulating only. As such, the top location may even be better.

Regardless of where the CPU is located on the motherboard I don't see how
you come to the conclusion that having the 'second' fan on the opposite
side from the motherboard is 'better', especially since that could mean
it's jammed packed, smack up against the case wall, depending on the case,
but, regardless, all I did was point it out. If you think that's wonderful
then so be it.

Again, he is trying to power an AT motherboard with an ATX PSU. The ON/OFF
problem is addressed in the PSU/MB connector adapter. See:

http://www.pcpowercooling.com/products/cooling/accessories/popups/indexatxtoatcable.htm

Great. All I said was it needs to be changed and that's one way to begin
the change.

The bigger problem is the motherboard.

But since we're discussing the PSU, this is irrelevant. [Besides, he
planned on putting an AT motherboard in an AT case.] Read the OP.

Since he was planning to put an AT motherboard in an AT case with an AT
power supply I haven't figured out why anyone is trying to get him to
change it to an ATX PSU to begin with. But since folks seem all fired set
on cramming ATX components into his AT case I thought I'd mention, as an
FYI, the problems of trying to do that with an ATX motherboard.

 

[ric]

Great. All I said was it needs to be changed and that's one way to begin
the change.

But the switch *isn't* changed. The adapters spade connectors connect
to the existing AT type switch.

Since he was planning to put an AT motherboard in an AT case with an AT
power supply I haven't figured out why anyone is trying to get him to
change it to an ATX PSU to begin with.

That's what happens when you don't read the whole thread. A poster
suggested that the OP get a couple of spare AT power supplies. That's
when the discussion of using ATX PSUs with AT motherboards began. It
was just in case his AT PSU fails and he cannot find a replacement.

 

[David Maynard]

David Maynard wrote:




But the switch *isn't* changed. The adapters spade connectors connect
to the existing AT type switch.

You're arguing semantics of no substance. The AT 'switch circuit' then,
since you're so bloody picky, doesn't work, as is, with an ATX supply.

I didn't propose a solution, I just warned the person to look out for that
and find a solution.

That's what happens when you don't read the whole thread.

No, it's what happens when you try and 'correct' things that don't need
'correcting' because everything I said is still valid regardless.

A poster
suggested that the OP get a couple of spare AT power supplies. That's
when the discussion of using ATX PSUs with AT motherboards began. It
was just in case his AT PSU fails and he cannot find a replacement.

And if he goes that route the PSU will be upside down and the power switch
will not work as it is configured for the AT PSU. 'How' the 'switch' is
altered is another matter and your solution looks fine.