400W PSU specs

[countdown]

I have a "400 watt" power supply unit (Olympic) with the following output
specs:

+3.3V 20A
+5V 20A
+12V 10A
-12V 0.5A
+5VSB 2A
-5V 0.5A

Is the 12V @ 10A the total combined output (ie 120W), or is this 10A each
for the standard and P4 connectors?

TIA

 

[Thomas Wendell]

As there is only one row "+12V @ 10A" it means it's 10A total on that
rail, ie. standard_+_P4 connector...


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[Zotin Khuma]

I have a "400 watt" power supply unit (Olympic) with the following output
specs:

+3.3V 20A
+5V 20A
+12V 10A
-12V 0.5A
+5VSB 2A
-5V 0.5A

Is the 12V @ 10A the total combined output (ie 120W), or is this 10A each
for the standard and P4 connectors?

TIA

It's probably the combined rating. In any case, are you sure you got
your figures right ? The total wattage of all the outputs you listed
add up to only about 300W (304.5W to be exact), and not 400W.

In most of the PSUs I've used and seen, the +3.3V supply is internally
derived from the +5V rail. So the overall rating is even less than the
combined total of all outputs rated separately. This is stated on the
stickers with something like "Total power from +5V & +3.3V should not
exceed XXX Watts", and XXX is usually the max load for the +5V rail
alone.

If your PSU is like this, it means that you cannot draw 20A *each*
from the 3.3V and 5V rails at the same time. This will further reduce
the total power rating below 300W.

 

[Dave C.]

As there is only one row "+12V @ 10A" it means it's 10A total on that
rail, ie. standard_+_P4 connector...

That seems kind of low for a 400W supply, more like a 300W. -Dave

 

[countdown]

It's probably the combined rating. In any case, are you sure you got
your figures right ? The total wattage of all the outputs you listed
add up to only about 300W (304.5W to be exact), and not 400W.

Those figures are direct off the label, and I was somewhat surprised that
the 12V output would be at this level on a "400W" power supply.

The only way I could get it to add up to ~400W was by taking into account
some more 12V amps for the P4 connector but I think it is highly unlikely
that the PSU is dual rail, as usually this would be mentioned (at least
with ATX12V1 etc).

 

[Guest]

I have a "400 watt" power supply unit (Olympic) with the
following output specs:

+3.3V 20A = 66.0W
+5V 20A = 100.0W
+12V 10A = 120.0W
-12V 0.5A = 6.0W
+5VSB 2A = 10.0W
-5V 0.5A = 2.5W

Add the maximum power ratings of the outputs and you get only 304.5W,
and keep in mind that most ATX supplies can't put out the maximum
calculated this way.

Is the 12V @ 10A the total combined output (ie 120W), or is
this 10A each for the standard and P4 connectors?

Some newer supplies have 2 separately limited +12V outputs, one for
the motherboard (rating for it will include the P4 connector), another
for the peripherals. So unless you left out the rating for any second
+12V output, this supply was grossly overrated for power.

 

[Lordy]

I have a "400 watt" power supply unit (Olympic) with the following output
specs:

Is it heavy