For gaming I serious advise the 91.31 driver. I have the same laptop as you, tried many drivers, did many benchmarkings, and this one is by far the most stable and by little, the better performing one. The newer drivers that came out after it (don't know why) have been showing poorer results on 3Dmark programs.
For gaming, at this time, definitly the 91.31.
As Borkar said, the 6800 Go will not work with drivers after 83.?? (I don't remember now, but I think it's 83.xx or 84.xx). For instaling newer drivers you have to update your bios to the 39.60 version. Be very carefull doing this, as you can permanetly inutilize your GPU. I did it with no problems.
I hope I helped. If you're going in with the flashing, check this forum for needed files and instructions:
http://www.laptopvideo2go.com/forum/index.php?
Good luck!