Replacement Power Supply

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Grinder

I've recently had a power supply on an older (windows 98 era) PC fail. The
replacements I'm finding online appear to be the right dimensions, but I'm
not sure about the motherboard connector. Are there multiple standards that
I have to worry about?

Thanks for your time and consideration.
 
I've recently had a power supply on an older (windows 98 era) PC fail. The
replacements I'm finding online appear to be the right dimensions, but I'm
not sure about the motherboard connector. Are there multiple standards that
I have to worry about?

Thanks for your time and consideration.
Click to expand...

A Windows 98 era PC would typically be "ATX" standard, which uses a 20-pin
connector with standard pinout with the following functions and colors:
http://69.36.189.159/usr_1034/atx_on.gif
That would be the "default" power supply configuration these days, what
you'd get if you bought one that didn't provide enough specs to make any
further determination about it.

OEMs like Compaq may deviate slightly on some colors, for example the 12V
might be blue instead of yellow. Dell in particular did something
inexcusable, used a standard ATX connector but used a proprietary pinout
that is incompatible, certain Dell PSU cannot be used on standard ATX
motherboards and vice-versa, the accompanying Dell motherboard could not
use a standard ATX power supply.

The odds are that your power supply is standard ATX and exactly matches
the above linked picture. The specs on the power supply label may also
clearly mention the voltages or at least a model number which can be used
to find power supply online. By the same token the motherboard make and
model can be input to a search engine to determine if it's standard ATX.

There was the older AT spec, but it was for the most part phased out by
the Win98 era... only a few motherboards, typically Matsonic/PCChips/etc
Super Socket 7 boards. Even those typically had both types of power
supply connectors on the motherboard, could run from either AT or ATX
power supplies.

If the above doesn't provide enough for you to make a determination you
can use a multimeter to measure voltages if possible, or post more
details of your system, power supply and motherbaord make, model.
 
A Windows 98 era PC would typically be "ATX" standard, which uses a 20-pin
connector with standard pinout with the following functions and colors:
http://69.36.189.159/usr_1034/atx_on.gif
That would be the "default" power supply configuration these days, what
you'd get if you bought one that didn't provide enough specs to make any
further determination about it.
Click to expand...
OEMs like Compaq may deviate slightly on some colors, for example the 12V
might be blue instead of yellow. Dell in particular did something
inexcusable, used a standard ATX connector but used a proprietary pinout
that is incompatible, certain Dell PSU cannot be used on standard ATX
motherboards and vice-versa, the accompanying Dell motherboard could not
use a standard ATX power supply.

The odds are that your power supply is standard ATX and exactly matches
the above linked picture. The specs on the power supply label may also
clearly mention the voltages or at least a model number which can be used
to find power supply online. By the same token the motherboard make and
model can be input to a search engine to determine if it's standard ATX.

There was the older AT spec, but it was for the most part phased out by
the Win98 era... only a few motherboards, typically Matsonic/PCChips/etc
Super Socket 7 boards. Even those typically had both types of power
supply connectors on the motherboard, could run from either AT or ATX
power supplies.

If the above doesn't provide enough for you to make a determination you
can use a multimeter to measure voltages if possible, or post more
details of your system, power supply and motherbaord make, model.
Click to expand...

Thanks -- that does match what I'm seeing. (Some colors are different, but
they match the potentials that are indicated.) The machine is garage build,
so I don't think I have to worry about Dell's chicanery.
 
First of all you haven't said if it is AT or ATX. Most of the newer ones
they sell are ATX. You can tell this by the power connectors on the old one
and on the board. The AT are in two parts from the supply and the ATX is
just in one part. Some boards can accomodate both which can be seen by the
female power receptors on the board. The ATX alternates between curved and
square shapes on both the male and female plug and receptor.
 
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