I can answer that one for you, musclecars&computers...my answer might not be complete, so others might want to add their comments...but I'll give it a shot!


Building a quality PSU might not be such an easy task... the PSU has to have stable rails & high efficiency at all voltages and all loads (low-med-high). Stable rails are a MUST for a stable computer... "high efficiency" saves energy (money!) & equally important generates....a LOT less heat... also contributing to stability plus the benefit in the "cooling department"... Important is a well thought of design... allowing the highest "combined power rating" as to the "advertized" total power rating....
and now I'm not even taking ATX & BTX 'specs, "modular cabling" & others into consideration..

A quality PSU is made of "quality" components.... and here I mean ALL components... high quality pcb,
resistors, capacitators, ic's, cabling, shielding, large & efficient heatsinks, quality low noise but good performing fans, fan controlling circuitry, protective circuitry, PFC,... you name it... saving costs on these
parts isn't a good idea... you lose quality... inevitably.... & thus either/and/or stability, efficiency, rated power and even long livety..... These components do cost a bit more...but they are wort it...

But.... the brand NAME always plays a big role as well...they are the ones who can as the 'max price forv their quality stuff...

Of course, like always, there might be some Chinese (or otherwise) company offering a Rock Solid
part at a very low price....even made of of decent parts.. that's just "economics".... people don't know the
brand, they often don't know if it is any good, they just buy it because it comes with the 'case or if the 'add
looks good.....

I you get lucky you can buy a real quality PSU this way... but rest assured... once it is tested as "good"
on the 'Net or in magazines, the price usually "soares up"...

Hope this answers your questions... (or part of them)...

TDR