ATX 12v 1.3 is actually a spec for PSU design.

"ATX12V 1.3

Introduced in April 2003 (a month after 2.0). This standard introduced some changes, mostly minor. Some of them are:

Slightly increased the power on 12 V rail.
Defined minimal required PSU efficiencies for light and normal load.
Defined acoustic levels.
Introduction of Serial ATA power connector (but defined as optional).
Guidance for the −5 V rail was removed (but it was not prohibited)."

http://www.formfactors.org/developer%5Cspecs% … TX12V_1_3dg.pdf

http://en.wikipedia.org/wiki/ATX

If the PSU can deliver the req'd power on 3.3V and 5V (20~25A on each should be fine for most old CPUs) it should work just fine. Modern PSUs tend to lower those in favor of the 12V rail(s).

So... 25amps on each 3.3 and 5 volts (+ line) and 15 amps on the 12 volt would be sufficient then?
I have found an PSU brand new. It's rated that and makes me think that it's not an 12volt1.3 but an 1.3 instead.

AFAIK "12V 1.3" and "ATX 1.3" are the same - I think technically it's supposed to say "12V 1.3" but a lot of manufacturers shorten things. 25A/ea for 3.3 and 5V is more than enough for SS7 or P3 (and probably for K7 too, depending on exactly what you're doing).

brostenen wrote:

So... 25amps on each 3.3 and 5 volts (+ line) and 15 amps on the 12 volt would be sufficient then?
I have found an PSU brand new. It's rated that and makes me think that it's not an 12volt1.3 but an 1.3 instead.

If you can, try posting the PSU's label, like this one:

Found a picture online of the label. It's even got -5volt line 😳
Think this is good enough for an SS7 system with an K6-3 400 and Voodoo3 3500 or GF2/TNT2-Ultra.
What's the verdict? 😀

Never heard of LC Power before. Doing a quick google search:

http://www.jonnyguru.com/forums/showthread.php?t=10062

Even on the PSU Database there are very little reviews about their units. http://www.realhardtechx.com/index_archivos/Page8401.htm

For a old computer it might be OK if they didn't skimp regulations for the most used rails. Can't really give it a OK or a drop, though.

I can't find pics of the guts from the LC Power HC420H-8, all I can tell you is that from a distance it smells like cheap chinese stuff.

Providing the label can be trusted, a 25A secondary rectifier on the +5V rail will be plenty enough for SS7 and PIII systems.

If you open the PSU and take pics of its guts I'll tell you much more about it.

Well. I have not bought it yet.
I did only ask whether this PSU is something I could use and what specs.
So I can't really open it. 😉 😁

Then I'd stay away from that thing. Better to spend a few more euros and get something reasonably decent, like a Be Quiet L8-300W or something like that.