I decided not to TEST the power supply. If you say you've never heard of MGE (local NY area stores and some on line places seem to have them popping up lately) its good enough for me... AND when I hold the bugger in my hands, it's LIGHT! The best things about it were the shiny chrome finish and the 120 mm extra blue LED fan on it.
So, I replaced it with a Thermaltake Purepower 420 W (dual fan) unit (and cut my palm on the corner of a PCB pulling out one last recalcitrant power connector). No fancy schmancy LED lit fans, but it's got two QUIET fans, and in reality, that counts more.
And, so far, no crashes or lock ups, except for the time I tried to move some of that rat's nest mass of wiring around to more convenient spots in the case... stupidly... with the power on and my kid playing something on it. Outside of that, it seems stable now. Of course, the real test is the weekend, when they go ape playing whatever online, offline, inline, outline, outright awful... on the PC. I'll post again after then to report on the acid test results for the Thermaltake's effect on stability.
Now, mind you, my other kid's comp, an older machine, has exactly the same PSU and his system has NEVER given him any trouble. So, if the system still hangs, I'm going to have to... sigh... investigate RAM prices further...
*EDIT* - I like the this particular Thermaltake unit because it is stable, trouble free, made by a KNOWN reputable manufacturer of such parts, and CHEAP!! From Newegg, it's only a tad over $40 (USD) after shipping.