To start, we took the XFX GTX285 from a stock 690MHz/1300MHz/1552MHz core/memory/shader stock overclock and pushed it to 756MHz/1476MHz/1584MHz core/memory/shader. Incredibly, this card would complete 3DMark2006 in 1/4 of the time with the memory running at 1501MHz, 3GHz effective!
Then, the CPU was overclocked from 3GHz to 3.7GHz and the SM2 and SM3 scores jumped considerably. At 3GHz, this GPU was being bottlenecked by the CPU. This system overclock yielded a solid 18.7k 3DMarks.
Switching over to the PNY GTX 285 and setting the CPU to 3GHZ, we managed to push the card from a stock overclock of 648MHz/1242MHz/1476MHz core/memory/shader to an amazing 777MHz/1458MHz/1588MHz overclock.
Overclocking the processor once again to 3.7GHz, the PNY GTX 285 scaled incredibly well, nearly knocking down 19k 3DMarks.
This just goes to show that a lot of overclocking is based just on luck. I would have thought due to the XFX GTX 285 featuring a much higher stock overclock, it would have overclocked much better. It turns out both cards walled at 1584MHz on the shader, but the PNY has a slightly faster core while the XFX has slightly faster memory.