in RivaTuner 2.06 what's new:
Added ForceWare 167.xx and 169.xx drivers families support. Please take a note that 2D/3D performance levels switching is broken in currently broken in these drivers, so adjusting 2D performance level settings (e.g. 2D clocks) via RivaTuner will also change 3D performance level settings and vice versa.

簡單說就是新版ForceWare驅動程式取消了內建2D/3D切換功能


解決方案:

手動設定profile教學:
http://www.vaguesoft.com/index.php?pageid=rt207

ptt熱心網友cp296633寫的教學:
http://kaobei.myweb.hinet.net/rivatuner/index.htm