twistedbrain said:
Paul thank You,
I have to say that I know about nothing about that, so what I'm going
to write
could be fully wrong, but I report only things (maybe false or
misunderstood)
I read, it is, I read that Active PFC enhance efficiency in some
different places
and (but it's unrelated - I think) I saw that 220 vattage instead of
110 could be
good for efficiency because in a comparartive table of most efficient
PSU there
were more model at 220 than at 110 and at 220 was given also the
category of
Platinum 80 (also if it was empty).
Anyway this last consideration about vattage is absolutely unsure and
unerliable,
insead, about Active PFC I read that in some different and also
normally reliable
places like Anandtech.
Active PFC helps the power company. It may cost the user a small amount
of efficiency. I don't think it is completely neutral in terms
of its effects on the user's power bill. The power supply still meets
its stated efficiency. My comment was more about the conflicting
nature of PFC - active power factor correction helps the power company,
but may not always work in the favor of the end user. If you look
at the power supplies sold in North America, there isn't the
same emphasis on PFC, and I don't think any of the supplies
I own, have PFC.
There could be a difference between efficiency at 110 versus 220 volts.
But in the case of the Seasonic, that particular one only operates
at 220 volts. I mentioned that, so that you'd check to see whether
your power source is 220V or not. If you're in a country using 110V,
then that particular Seasonic could not be used.
If you have room in the computer case for a regular sized ATX supply,
there are supplies with a higher efficiency than 80%. This model, for
example, claim 87%. It appears to use a DC-DC converter, to convert
12V to 3.3V and 5V. So the main part of the supply is just a 12V
circuit. It means the path to 3.3V and 5V, goes through two conversion
steps.
http://www.seasonicusa.com/X.htm
AC ---- DC --+----------12V
|
+----DC----3.3V/5V
Scroll down, and look at the test results carefully. This new
design works best, if there is minimal 3.3V/5V loading. So for
computers that draw most of their power from 12V, the supply
gets around 90% efficiency. If you heavily load the 3.3V and
5V rails, the efficiency drops to 85%. You could see
very good results here, as long as the motherboard doesn't
need too much to run the chipset and peripheral chips.
Of course, you need room in your computer case to fit this.
You may want to verify the dimensions, and see how well
it fits your computer case.
http://www.jonnyguru.com/modules.php?name=NDReviews&file=print&reid=169
3.3V @ 1A, 5V @ 1A, 12V @ 10A, 23C temp 90.5% efficient
3.3V @ 14A, 5V @ 14A, 12V @ 1A, 29C temp 87.5% efficient
3.3V @ 14A, 5V @ 14A, 12V @ 1A, 35C temp 85.0% efficient
So you can get some fairly good numbers, if price is no object.
The price here is $180 USD.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817151088
Paul
.