Stefek Zaba wrote:

Disconnect PSU, short its ATX-pwr pin 14 (green wire) to adjacent black
(ground) pin. Nothing. Dim sausigio. I was sure 'normal' ATX PSUs were
supposed to switch-on while pin 14 was grounded?

Yup, indeedy

And indeed, nipping
down the road to PCWorld (I know, I know...) and picking up a less
fancy-pants ATX PSU (still 450W-nominal, yada yada) yields one which not
only comes on full with pin 14 grounded, but powers up the mobo
perfectly well.

Me thinks you have your answer....

I call that more or less conclusive evidence of misbehaviour by the
Tagan PSU, but just before I make an arse of myself sending it back to
the fine people at overclockers.co.uk - does anyone with relevant
PC-assembly experience want to clue me in on any simple oopsie?

Lets assume that your turned on the nice rocker switch on the back of
the PSU for a moment... ;-)

And it has not got an input voltage selector slider thingy that is slid
(or not slid) in the wrong (or right) place, nor somewhere betwixt the
two of them, then, your PSU is in need of buttering and eating...

(i.e. is toast)

Oh, and in the realms of "obvious when you think about it": the
processor fan, running under the mobo's own speed control, is doing nice
slow revs, and the hs heatpipes are barely warm to the touch. But as
there's no case fan moving any air, the *memory* modules are letting off
'noticeable' amounts of heat! (Kinda reasonable the moment you think
about it, since Memtest86 is full-on accessing all of RAM just as fast
as the memory controller will let it!). An infra-red thermometer claims
to see temps of 55C or so on the DIMMs (and on a few spots of the
similarly unfanned vidcard). Still, if they survive a 'burnin' like
this, they should be happier in the case with reasonable airflow!

55 hardly counts as warm in reality... I would rather have em a bit
cooler, but they will survive that indefinitely (well until your shiny
new processor seems hopelessly inadequate for running solitaire, and
hence you upgrade it to something that won't fit in the motherboard and
wants DDR7 RAM or some such). Oops my MB expansion potential cynicism is
showing ;-)

--
Cheers,

John.

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