<< What sounded fishy to me was how this one nVidia card was given "special enhancements to improve performance". If they're not referring to overclocking, they have some kind of special drivers that do something to either actually enhance performance or degrade quality for sake of speed. (We've been there before.)
In either case, you'd be stuck with their drivers if you want this "special enhancement technique." >>
The performance enhancement is an overclock. But since Gainward guarantees it to run at that speed it's not really an overclock, but the core/ram are set to run at a higher speed by Gainward's drivers in their enhanced performance mode. I used to own a Gainward GF2 Pro/450 Golden Sample card and the Gainward drivers for that card allowed it it run at it's stock speed of 200/400, or in Gainward's enhanced performance mode at 220/444.