Very sorry for my english.......
Ok , i'm download the new drivers for my 6800GT (81.94) , The bug is here.
But with the 81.87 the bug is not here.....
Desinstallation the 81.94 , and use the "regedit" for deleted the "traces" of the drivers.
Reboot and reinstallation 81.87 , the bug is out with the drivers (for me)......
http://www.3dchips-fr.com/fichiers/352/forceware_v81_87_win2k_xp.html
Good fly all.