OCIA.net has posted an article on Unlocking / Overclocking the NVIDIA GeForce 6800. Below is a direct quote from the article:
"As you may know, one of the main differences between the 6800 base model and the GT version is the fact that the GT version comes with a total of 16 pixel pipelines, whereas the 6800 only has 12. I began reading on various message boards that some people were actually able to unlock the remaining four pixel pipelines on their 6800 cards for a total of 16, matching that of the GT model. This seemed completely reasonable, as the 6800 is more or less a watered-down version of its GT counterpart. My mind began to roam, wondering if it would be possible to unlock / overclock this base model XFX 6800 to the GT level, a card that cost nearly $130 more. And so my quest began..."
Direct Link
"As you may know, one of the main differences between the 6800 base model and the GT version is the fact that the GT version comes with a total of 16 pixel pipelines, whereas the 6800 only has 12. I began reading on various message boards that some people were actually able to unlock the remaining four pixel pipelines on their 6800 cards for a total of 16, matching that of the GT model. This seemed completely reasonable, as the 6800 is more or less a watered-down version of its GT counterpart. My mind began to roam, wondering if it would be possible to unlock / overclock this base model XFX 6800 to the GT level, a card that cost nearly $130 more. And so my quest began..."
Direct Link