On Mon, 23 May 2011 12:41:19 -0700 (PDT), KenO
wrote:

"What I look for is power factor correction. *That will drop the
efficiency somewhat, but is well worth it (and will soon be
mandatory).
Any idea when it will become mandatory?

In Europe, IEC 555-2 currently requires power factor correction to
reduce harmonics on power mains in power supplies. It's been around
for at least 15 years.

I don't know anything about the US status. Googling returned a muddle
which will require more time to untangle than I'm willing to burn.
Sorry(tm).

"I forgot exactly what I used: www.formfactors.org/developer/specs/
ATX12V_PSDG_2_2_public_br2.pdf
Tried to use the link but only got "404. That’s an error."

Very strange link. See ATX 2.2 link at:
http://www.formfactors.org/FFDetail.asp?FFID=1&CatID=2
The URL is a mix of / and \ in the path. That usually works, but not
this time. There are some links he
http://en.wikipedia.org/wiki/ATX#External_links
which seem to work better. Here's my copy in case you can't get the
link to work:
http://802.11junk.com/jeffl/crud/atx2_2.pdf

Do you know who makes the Dell PSU with the 120mm fan?

It won't work for building your own machine. The case has exactly one
120mm fan and it's not inside the power supply. It's near the bottom
of the case and acts as an air intake. The hot air gets blown out
through the power supply vent holes.
http://img.villagephotos.com/p/2003-7/271271/Opt960%20Inside2.jpg
The fan is the black thing above the disk drives. Air flow is from
left to right. There's no fan in the power supply.


More on PFC
http://www.nist.gov/pml/quantum/power_121509.cfm
http://www.xbitlabs.com/articles/cases/display/atx-psu5.html
This should explain power factor:
http://www.xbitlabs.com/articles/cases/display/atx-psu5_3.html#sect0
http://www.silverstonetek.com/tech/wh_pfc.php
More he
http://en.wikipedia.org/wiki/Power_factor
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558