[snipage]
The purpose of trying a 512MB stick of RAM in your machine,
is to ensure that no BIOS issue can possibly take exception
to the amount of RAM offered.

On a machine that new, there shouldn't be a problem really.
But at this point, I would try the single stick of 512MB
until the machine shows you a BIOS screen, and otherwise
behaves in a "responsible manner".

I just feel at this point, the locus of symptoms are better
explained by a BIOS issue, than some external issue. As sooner
or later, all these ATX supplies you've been testing,
at least one of them should have worked...

You can use your multimeter to verify this stuff too.
Even I would have trouble, identifying good test points
to use for verification. Only DFI (Diamond Flower motherboards),
provided actual scope testpoints soldered to the motherboard,
with voltage legends silk-screened next to it, to make
home verification of voltage levels easy. Other companies
could at least put plated holes in the mobo with a silk
screen next to them, to make test point checking easier.
That wouldn't cost them anything to do (just a few drill holes,
which costs buttons in the grand scheme of things).

On this particular motherboard, they used holes filled with
solder for the monitoring points. You touch your multimeter
red clip to those and measure. The black clip on your multimeter,
can go to a grounded screw on the I/O Plate area if you want.

http://i4memory.com/reviewimages/mot..._utx58_dmm.jpg

I don't like to use multimeter probes on a power
supply, and get the probe tips too close to one another.
That's why I clip the ground lead onto an I/O screw
when doing this sort of thing.

Paul

I have the MOBO manual PDF. It has a two page long diagnostic flow chart
that I will spend time on first.

After I go back to flowchart I find short between frame ground and all PCI
pins. This requires further study.

The DVD R/W drive is connected to frame. Disconnect SATA data cable, no PCI
short to frame ground. WFT? Have other SATA cable. Try that.

Good SATA data cable does not give PCI short to frame ground. Two bad SATA
data cables give PCI short to frame ground. Progress?

Paul, not all SATA data cables are the same. Why?