ATX Power Supply

Not exactly networking related but I'm sure someone will offer advice.

I want to use an ATX case and PSU to mount some IDE hard drives and
also to supply power but I don't particularly want to instal a
motherboard.

Is there a simple way to get the PSU to power up without a
motherboard.

Geoff Lane

Geoff Lane wrote in message
(E-Mail Removed):

> Not exactly networking related but I'm sure someone will offer advice.
>
> I want to use an ATX case and PSU to mount some IDE hard drives and
> also to supply power but I don't particularly want to instal a
> motherboard.
>
> Is there a simple way to get the PSU to power up without a
> motherboard.

Yes. You short one of the pins to ground. I *think* it's pin 14, but for
heaven's sake check this before you knacker a PSU!

Geoff Lane wrote:

> Not exactly networking related but I'm sure someone will offer advice.
>
> I want to use an ATX case and PSU to mount some IDE hard drives and
> also to supply power but I don't particularly want to instal a
> motherboard.
>
> Is there a simple way to get the PSU to power up without a
> motherboard.
>
> Geoff Lane

Short pin 14 (green) to either pin 15, 16 or 17 (black).

BTW, better to ask this sort of thing in uk.comp.homebuilt.

HTH

Chris

--
Remove prejudice to reply.

In message <44948c89$0$3534$(E-Mail Removed)>, Martin
Underwood <a@b.?.invalid> writes
>> Is there a simple way to get the PSU to power up without a
>> motherboard.
>
>Yes. You short one of the pins to ground. I *think* it's pin 14, but for
>heaven's sake check this before you knacker a PSU!
http://www.helpwithpcs.com/courses/p...nc-pinouts.htm
>
>

--
Clint Sharp

On Sun, 18 Jun 2006 08:19:59 GMT, Chris Whelan
<(E-Mail Removed)> wrote:

>Geoff Lane wrote:
>
>> Not exactly networking related but I'm sure someone will offer advice.
>>
>> I want to use an ATX case and PSU to mount some IDE hard drives and
>> also to supply power but I don't particularly want to instal a
>> motherboard.
>>
>> Is there a simple way to get the PSU to power up without a
>> motherboard.
>>
>> Geoff Lane
>
>Short pin 14 (green) to either pin 15, 16 or 17 (black).
>
>BTW, better to ask this sort of thing in uk.comp.homebuilt.
>
>HTH
>
>Chris
Do you also need to link 6 and 8 (Power OK to +5v) to get a stable 5v
supply?

PeeGee
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The reply address is a spam trap. If you need to reply directly, put the UK where it should be - first.

"PeeGee" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> On Sun, 18 Jun 2006 08:19:59 GMT, Chris Whelan
> <(E-Mail Removed)> wrote:
>>Geoff Lane wrote:
[snip]
>>> Is there a simple way to get the PSU to power up without a
>>> motherboard.
>>
>>Short pin 14 (green) to either pin 15, 16 or 17 (black).
>>
>>BTW, better to ask this sort of thing in uk.comp.homebuilt.
>
> Do you also need to link 6 and 8 (Power OK to +5v) to get a stable 5v
> supply?

No, you must not do that. PWR_OK is a PSU output signal that is asserted to
indicate that the main outputs (+3.3V, +5V and +12V) are OK.

ATX PSUs are likely to behave badly (eg poor regulation) if there is
insufficient load on the main outputs. The minimum current for each output
should be specified.

Alex

Alex Fraser wrote:

[...]

> ATX PSUs are likely to behave badly (eg poor regulation) if there is
> insufficient load on the main outputs. The minimum current for each output
> should be specified.

Indeed, but the OP did say he was using this setup to power "some" HD's...

Chris


--
Remove prejudice to reply.

"Chris Whelan" <(E-Mail Removed)> wrote in message
news:Vkblg.59727$(E-Mail Removed)...
> Alex Fraser wrote:
> [...]
>
>> ATX PSUs are likely to behave badly (eg poor regulation) if there is
>> insufficient load on the main outputs. The minimum current for each
>> output
>> should be specified.
>
> Indeed, but the OP did say he was using this setup to power "some" HD's...

Yes, and that is probably fine. I was mainly addressing PeeGee's comment
about what is needed "to get a stable 5v supply".

Alex

On Sun, 18 Jun 2006 12:13:27 +0100, "Alex Fraser" <(E-Mail Removed)>
wrote:

>"PeeGee" <(E-Mail Removed)> wrote in message
>news:(E-Mail Removed).. .
>> On Sun, 18 Jun 2006 08:19:59 GMT, Chris Whelan
>> <(E-Mail Removed)> wrote:
>>>Geoff Lane wrote:
>[snip]
>>>> Is there a simple way to get the PSU to power up without a
>>>> motherboard.
>>>
>>>Short pin 14 (green) to either pin 15, 16 or 17 (black).
>>>
>>>BTW, better to ask this sort of thing in uk.comp.homebuilt.
>>
>> Do you also need to link 6 and 8 (Power OK to +5v) to get a stable 5v
>> supply?
>
>No, you must not do that. PWR_OK is a PSU output signal that is asserted to
>indicate that the main outputs (+3.3V, +5V and +12V) are OK.
>
>ATX PSUs are likely to behave badly (eg poor regulation) if there is
>insufficient load on the main outputs. The minimum current for each output
>should be specified.
>
>Alex
>
Ok, just thought I'd ask. I've since spotted the 3.3v "sense" is
permanently wired!

PeeGee
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The reply address is a spam trap. If you need to reply directly, put the UK where it should be - first.

On Sun, 18 Jun 2006 12:06:13 GMT, Chris Whelan
<(E-Mail Removed)> wrote:


>> ATX PSUs are likely to behave badly (eg poor regulation) if there is
>> insufficient load on the main outputs. The minimum current for each output
>> should be specified.
>
>Indeed, but the OP did say he was using this setup to power "some" HD's...

Yes, that is correct, I only want the 12v supply.

I've got a plan of the ATX connector output should for the correct
pins to short out.

Thanks,

Geoff Lane