Use G200clk shortcut (step by step).............here

[Miranda]

Ok,
After downloading it, you double-click on it.
There will be your current clock settings (default) of you card.
Exit it.


Right click on the .exe program and go to Properties
On Properties, go to program tab and type on Command line after everything and a space:
/1 XXX

XXX is for example: 280

choose to close on exit and run minimized.
Close, cut it and past on Start/Programs/Starup.

Enjoy!
Miranda

PS: I suppose you know the pll clock you prefer.....