That sounds like the Sempron devbox I got running here. Eventually used an Asus barebone: Pundit P2-AE2

Very happy with it (after replacing the default fans)

Edit: Review at Sudhian

Bit off-topic, but does the passive (PowerColor) X1950 Pro need the extra power connector hooked up?

Don't forget the Sapphire 2600 XT

Fairly 'complete' review on the Abit Forums

As for the 2600XT, I am waiting for the Sapphire 2600 XT Ultimate Edition to become available (why can't Sapphire have proper images on their own site instead of the pictures of the boxes...)

Do the G0 stepping Q6600s run at 1333MHz by default, or are they also rated at 1066MHz like the older stepping? (of course, I realize you are saying they will default to 1333MHz regardless if placed on a P35-based board, but my question remains). Q6600 will be 1066 MHz. Nice Overview from Anandtech .

Not much of use for the topic starter, but for completeness sake:

Powercolor has a very nice silent X1950 Pro as well.

As promised, temperature figures here (not staying around 62 though)

Reviews: Overclock 3D, The Guru of 3D, Trusted Reviews...

Looking for something similar, and currently the XFX GeForce 8600 GT is in favor. Will post links later (don't seem to be able now as it is my first post).