I picked up a 256mb version yesterday from a dealer here in Paris. It's by PixelView and has lots of funky "tuning" features such as a bright blue illuminated fan and all that crap.
Anyway, I plugged it in last night and it runs great. Dual-screen no problem at all. It runs about as fast as the Quadro4-980XGL.
I too get the viewport refresh problem; switching from persp to 4-view and back but it seems a quick play with the timeslider fixes it no problem. Another minor pain is if I have Maya open at the same time as QuickTime and drag a Maya window over the QT window, QT crashes.
Still - it's nice to have both monitors up and running again!
I was thinking that I would sell the FX5700 on eBay when the Quadro is repaired, but I like it so much thatI think I'll hang onto it and build my wifes replacement PC around it.
That'll do donkey... that'll do...