I own a 7600GS. It's an AGP-model, not PCI-e.
The brand is Club-3D, and it has active cooling and also an extra powerplug (standard molex).
Mine is currently running at 470MHZ core and 914MHZ memory and it's stable with a maximum temp under load of 55 degrees celcius. It idles at 34 degrees celcius.
No artifacts whatsoever when playing games or running 3d-mark.
From what I've read on the internet, I came to understand that many 7600GS don't go as high as mine, but maybe it's because most of them are with passive cooling and no additional powerplug?
It's running 2323 points in 3dmark '06, and exactly 4444 in '05. Quite nice if you ask me.
I also never overclocked with small steps at a time. I simply used the Coolbits registery setting (
Click!) to unlock the factory overclocking tools in the NVidia classic control panel. Then I clicked the button "Detect optimal frequencies", at it came up with 460/900. I first tried it with those settings, and it was rockstable, so I added 10MHZ, both for RAM and VPU.