I still prefer Rage3D Tweak for the simple "OEM" look
:camera:.
If you don't need the actual tweak schtuff just select the o'erclock component with the "Nothing" skin. I recommend changing the FontHeight in the Nothing.Inf from 12 to 11 first, to match the ATI tabs, or alternately edit the registry afterwards and also enable the ATI tab integration.
[HKEY_LOCAL_MACHINE\SOFTWARE\Registry Tweak\ATI]
"GUID"="{700B1221-CAFF-11d1-B9DE-000000001B1B}"
"Disable"=dword:00000000
Then you can disable the ATI tray icon and just use Rage3D Tweak's (which can be changed to something else with registry editing if you like).