VR-Zone have a review up on this new NV18 card, they have gone one step further to set the core and memory clock higher than official speed recommended by NVIDIA. The usage of the faster 2.8ns DDR SDRAM on budget card like the NV18 is definitely interesting. From the default core and memory speed at 300/600Mhz, the reviewer was able to overclock the card to 390/740Mhz.
Check it out
http://www.vr-zone.com/reviews/Triplex/TX680/