Mark Twain wrote:
I lightened the picture of the 780:

http://i67.tinypic.com/9ieqhl.jpg

I don't notice anything else on the
780 besides those flanges, The 8500
also has flanges but they aren't
uniform, however the screw pattern
are the same.

http://i63.tinypic.com/347jogk.jpg


So if it has a slider set it to 110V?
and should I leave the power switched
on or do I have to switch it on/off each
time?

Thanks,
Robert

When an ATX PSU has the switch on the back,
you leave it at "1" or "ON".

When a supply is "ON" at the back, the +5VSB
rail is always powered. On my newer machine, this
wastes 1.3W of electricity.

If the machine is "ON" at the back and sleeping
(RAM contents preserved, no fans running), that
uses 7.5W of electricity.

The power button on the front of the computer
is the "soft" power button. It causes the PSU
to go to the full power state, so both halves
of the PSU run.

When you select shutdown in Windows, that turns
off the big half of the supply, but leaves
the +5VSB running. And a shutdown uses 1.3W,
whereas a selection of Sleep (wakes up fast)
is 7.5W.

The amount of Sleep power, is a function of the
amount of memory. My typing machine uses 5W
while sleeping, the test machine uses 7.5W.

Some older supplies were less efficient. They
wasted enough power, that when you woke them
from sleep, a puff of warm air would initially
come out of the PSU housing. And that's proof
that the +5VSB heatsink was pretty hot inside.
While it was sleeping.

The supplies I have now, don't have a thermal
signature at startup, so less power is wasted.
And the measurement shows the magnitude of
power involved.

You use the switch at the back, if and when you
want the consumption to be exactly 0.0 watts.
You do shutdown first (drops to 1.3W), then
go to the back of the machine and switch it off
to 0.0W loading.

Your machines without the switch, would always
have the +5VSB running. With power loads depending
on what they're doing, like in the examples above.

Paul