Does higher wattage power supply equal higher electricity drain????

I'm debating to use either a 400 watt or 500 watt power supply for my
Athlon xp system. This is a name brand, amd aproved power supply. I know
the 400 watt is enough power for my system, but I was wondering if I were
to buy the 500 watt power supply instead would it drain my electricity than
the 400 watt one just because it is 100 watts more powerful? I want to
keep my electric bills down but would also like to have a power supply I
can use on a later system. So I guess simply I am asking does the higher
wattage in the power supplys affect how much electricity is drained?
Thanks!

wrote in message
...
I'm debating to use either a 400 watt or 500 watt power supply for my
Athlon xp system. This is a name brand, amd aproved power supply. I know
the 400 watt is enough power for my system, but I was wondering if I were
to buy the 500 watt power supply instead would it drain my electricity
than
the 400 watt one just because it is 100 watts more powerful? I want to
keep my electric bills down but would also like to have a power supply I
can use on a later system. So I guess simply I am asking does the higher
wattage in the power supplys affect how much electricity is drained?
Thanks!


a powersupply just delivers what's demanded of it...
so your machine will use *approximately* the same amount of power
with a 500 watt supply as it would with a 400 watt supply

to make any significant difference on your electric bill

wrote in message
...
I'm debating to use either a 400 watt or 500 watt power supply for my
Athlon xp system. This is a name brand, amd aproved power supply. I know
the 400 watt is enough power for my system, but I was wondering if I were
to buy the 500 watt power supply instead would it drain my electricity
than
the 400 watt one just because it is 100 watts more powerful? I want to
keep my electric bills down but would also like to have a power supply I
can use on a later system. So I guess simply I am asking does the higher
wattage in the power supplys affect how much electricity is drained?
Thanks!


Maybe a buck or two a month from heat losses of the larger componants in a
500 watt. AC units would also be taxed slighty but all in all insignificant.
It would make a real difference in comparing a 1000watt PSU to a 400.

Lane

On Sat, 15 Nov 2003 17:23:52 GMT, "
wrote:

I'm debating to use either a 400 watt or 500 watt power supply for my
Athlon xp system. This is a name brand, amd aproved power supply. I know
the 400 watt is enough power for my system, but I was wondering if I were
to buy the 500 watt power supply instead would it drain my electricity than
the 400 watt one just because it is 100 watts more powerful? I want to
keep my electric bills down but would also like to have a power supply I
can use on a later system. So I guess simply I am asking does the higher
wattage in the power supplys affect how much electricity is drained?


No.

Lane Lewis wrote:

So I guess simply I am asking does the higher
wattage in the power supplys affect how much electricity is drained?
Thanks!


Maybe a buck or two a month from heat losses of the larger componants in a
500 watt.

LOL.

In reality, the 500w would have, given identical design, larger components
and heatsinks and thus run cooler (running at the same output wattage as
the 400w), and have *less* heat losses than the 400w PSU.

"ric" wrote in message ...
Lane Lewis wrote:

So I guess simply I am asking does the higher
wattage in the power supplys affect how much electricity is drained?
Thanks!


Maybe a buck or two a month from heat losses of the larger componants in
a
500 watt.

LOL.

In reality, the 500w would have, given identical design, larger components
and heatsinks and thus run cooler (running at the same output wattage as
the 400w), and have *less* heat losses than the 400w PSU.


Nope. Given that niether is overloaded and supplying the same amount of
power the 500 watt will use more. Imagine a 50 watt draw on a 100w PSU and a
50 watt draw on a 1000watt PSU. The thousand watt has larger componants and
will draw more. This is one of the reasons for matching up componants. There
is not much difference in a 400 and 500 watt, but the idea holds true.

Lane

The power supply will only use what it needs to power your devices, no more.

--
DaveW



wrote in message
...
I'm debating to use either a 400 watt or 500 watt power supply for my
Athlon xp system. This is a name brand, amd aproved power supply. I know
the 400 watt is enough power for my system, but I was wondering if I were
to buy the 500 watt power supply instead would it drain my electricity
than
the 400 watt one just because it is 100 watts more powerful? I want to
keep my electric bills down but would also like to have a power supply I
can use on a later system. So I guess simply I am asking does the higher
wattage in the power supplys affect how much electricity is drained?
Thanks!

Nope. Given that niether is overloaded and supplying the same amount of
power the 500 watt will use more. Imagine a 50 watt draw on a 100w PSU and
a
50 watt draw on a 1000watt PSU. The thousand watt has larger componants
and
will draw more. This is one of the reasons for matching up componants.
There
is not much difference in a 400 and 500 watt, but the idea holds true.




hold on a minute...

if , for example you have a 1 watt , 500 ohm resistor
and replace it with a 5 watt, 500 ohm resistor
the 5 watt resistor will *not* draw any more power than the 1 watt


so if you have a supply with components rated at higher power...
it does not necessarily mean the supply will draw any more power


*however* there are variations in overall efficiency depending on how much
of the rated output a psu is actually producing.


typically supplies operate most efficiently at the higher end of their
overall
rating so there is some truth that a 150 watt supply operating at 100
watts
for example could be more efficient than a 1000 watt supply operating at
100
watts but it is not really due to the power ratings of the components
per se
it is more due to the powerfactor and characteristics of the transformer
plus the high-frequency conversion circuitry itself

this whole thing can get quite complicated but suffice it to say that
there would be no significant difference in electrical costs to operate a
400
vs a 500 watt supply

"philo" NONphiloNONplazaearthNONcomNON wrote in message
...



Nope. Given that niether is overloaded and supplying the same amount of
power the 500 watt will use more. Imagine a 50 watt draw on a 100w PSU
and
a
50 watt draw on a 1000watt PSU. The thousand watt has larger componants
and
will draw more. This is one of the reasons for matching up componants.
There
is not much difference in a 400 and 500 watt, but the idea holds true.




hold on a minute...

if , for example you have a 1 watt , 500 ohm resistor
and replace it with a 5 watt, 500 ohm resistor
the 5 watt resistor will *not* draw any more power than the 1 watt


so if you have a supply with components rated at higher power...
it does not necessarily mean the supply will draw any more power


*however* there are variations in overall efficiency depending on how
much
of the rated output a psu is actually producing.


typically supplies operate most efficiently at the higher end of their
overall
rating so there is some truth that a 150 watt supply operating at 100
watts
for example could be more efficient than a 1000 watt supply operating at
100
watts but it is not really due to the power ratings of the components
per se
it is more due to the powerfactor and characteristics of the transformer
plus the high-frequency conversion circuitry itself

this whole thing can get quite complicated but suffice it to say that
there would be no significant difference in electrical costs to operate a
400
vs a 500 watt supply

Additional heavier circuitry, larger mosfets and other components, all use
more power when turned on. It gives you more power availibilty but at a
price. I don't think my statement of a buck or two a month is out of line.
Easily checked though with an AC ammeter.

Lane

On Sun, 16 Nov 2003 04:05:50 GMT, "Lane Lewis"
wrote:


this whole thing can get quite complicated but suffice it to say that
there would be no significant difference in electrical costs to operate a
400
vs a 500 watt supply

Additional heavier circuitry, larger mosfets and other components, all use
more power when turned on. It gives you more power availibilty but at a
price. I don't think my statement of a buck or two a month is out of line.
Easily checked though with an AC ammeter.


Many of the larger PSU manufacturers provide efficiency specs, they
should be helpful in determining the power usage.

Generally larger components will not consume more power. The only
time a switching power supplie's efficiency is significantly increased
is if powering a known, fixed load, allowing tuning. Otherwise the
difference isn't worth consideration, especially not when comparing a
400W and 500W PSU from same manufacturer, which if made for the same
target/use, the two may be quite similar if not almost identical
inside, and in efficiency.



Dave