You’re definitely welcome. Test-smesh?
Was going to just send you a video card. (Even though I may have forgotten that you’re in Land-of-Kiwi.)
Only time I’ve ever seen artefacts like that, was with a single video card that was definitely failing.
All cards out except the one AGP (or with the PCI card in by itself… but not both in together).
Then make certain that all card slots are clean, down inside as well (no little dust or tiny errant hairs)…
and the contacts on both the cards freshly cleaned. Still be interested in what Apple Hardware Test
might report, testing with both cards individually.
*I found a small hair on a board inside a Komplete Audio 6 interface recently and after removal &
blowing the internal boards out completely… reassembled it and it has worked flawlessly ever since.
Suppose ovalking’s questionable PSU (and resultant bizzare RF interference) idea could be possible.
Place the booted QS up against the also-booted Beige G3 and see if you also get artefacts on the Beige
G3’s display. If so, still wouldn’t prove PSU as culprit… but something in the QS. AirPort card present or
the connector for one, properly secured and not out of place... grounded to something? Other cables
running across the door hinge-point in good shape?
Sorry, not more help. I’m out of ideas.
Anybody else?
Just too odd that both cards provide same prob.