[ChrisRay]

I think you might want to read up on clock domains and rivatuner. All Geforce 6 + series are capable of multiple clock domains but only the Geforce 7 series uses it by default. Also the way the overclocking scales on the Geforce 7 series isnt a per mhz value. Having a 450 core I believe actually scales to 459. The bios only recognises certain clocks and will automatically round them up to the nearest clock domain the bios recognises.