Alexey (RivaTuner programmer) made an interesting find -- Non ultra 6800's may have 1 or more disabled vertex processors.
http://content.guru3d.com/newsitem.php?id=1828
"Yesterday I've received new MSI 6800 instead of old Leadtek 6800, which died during unsuccessfull BIOS flash (Thanks a lot to Andrew Worobiew for providing new one). So I was able to continue NV4x internals exploration and found some extremely interesting facts.
First, our assumption about dyad based pipeline control seems to be wrong. Pipelines are still masked at quad level rather than on dyad level. So RT's pipeline control tab is redesigned and will look a bit different comparing to the screenshots walking in the net.
Second (and the most interesting), I've found the way to detect and enable/disable active vertex units on NV40 boards. The most surprising fact is that _ALL_ 6800 non-Ultra boards I've seen have at least one disabled (bad?) vertex processor too, so just 5 or less of them are active instead of 6 in Ultra models. Like quads, vertex processors can be also disabled at both software and hardware levels, so RT will help you to unlock them only in the first case. Currently we're collecting 6800GT statistics to understand if these processors are full 6800U analogues or they also have ripped configuration due to disabled vertex processors. Also, we hope that NVIDIA will clarify specs for 6800NU/6800LE/6800GT boards, because currently we see the boards with different amount of disabled vertex units sold as regular 6800 model.
That is why I'd like to warn everybody going to buy non-Ultra 6800. We've already detected $350+ OEM Leadtek 6800 boards in Russia, which have 2 disabled quads and 2 disabled vertex processors. So if you're going to buy such board, we strictly recommend you to wait for new RT release and to verify the board before (or immediately after) purchasing. Otherwise you may get a regular 6800LE for a fabulous price."
http://content.guru3d.com/newsitem.php?id=1828
"Yesterday I've received new MSI 6800 instead of old Leadtek 6800, which died during unsuccessfull BIOS flash (Thanks a lot to Andrew Worobiew for providing new one). So I was able to continue NV4x internals exploration and found some extremely interesting facts.
First, our assumption about dyad based pipeline control seems to be wrong. Pipelines are still masked at quad level rather than on dyad level. So RT's pipeline control tab is redesigned and will look a bit different comparing to the screenshots walking in the net.
Second (and the most interesting), I've found the way to detect and enable/disable active vertex units on NV40 boards. The most surprising fact is that _ALL_ 6800 non-Ultra boards I've seen have at least one disabled (bad?) vertex processor too, so just 5 or less of them are active instead of 6 in Ultra models. Like quads, vertex processors can be also disabled at both software and hardware levels, so RT will help you to unlock them only in the first case. Currently we're collecting 6800GT statistics to understand if these processors are full 6800U analogues or they also have ripped configuration due to disabled vertex processors. Also, we hope that NVIDIA will clarify specs for 6800NU/6800LE/6800GT boards, because currently we see the boards with different amount of disabled vertex units sold as regular 6800 model.
That is why I'd like to warn everybody going to buy non-Ultra 6800. We've already detected $350+ OEM Leadtek 6800 boards in Russia, which have 2 disabled quads and 2 disabled vertex processors. So if you're going to buy such board, we strictly recommend you to wait for new RT release and to verify the board before (or immediately after) purchasing. Otherwise you may get a regular 6800LE for a fabulous price."
