I had a 6800 Ultra before - it was a review sample on "permanent loan" from a friend and I thought it was about time I returned it in fully working condition! Great card but the cooler noise to used to piss me off - even at 25% speed it had this horrible grinding quality.
The 7600GT is pretty much as fast and completely silent. I suspect there is a lot of overclocking headroom too. Couldn't say no for £115 - what a bargain!
It's fantastic. In the position shown it really catches a nice cool draft from the exhaust fans. Idle temps are sub-50C and I can push it to 605/1640MHz without having to have any of my case fans above 5V. Think I'll get a Coolermaster Hyper 6 for the CPU next.
I have a feeling that the core will go quite a bit higher - at the moment it isn't artifacting/freezing at above 600MHz, but stuttering instead. Seems to be a power supply issue.