best windows software for FSB/mult adjustment for nforce 4?

[Devistater]

I'm looking to adjust my FSB and multiplier on my nforce 4 motherboard, while I'm running windows, without a reboot.

I want to normally clock my stuff most of the time, then when I do games, clock it up a bit.

Right now I'm running my amd64 4000+ san diego core overclocked to 2.750 ghz and 11 multiplier (air cooling with 120mm fan). My bus speed is 250mhz with a 4x multiplier so I can do 1000mhz HT.

The normal speed for this chip/system is:
200mhz x 12 (2.400 ghz), and bus 200mhz with 5x multiplier.

I prefer to use a software that I don't have to have running all the time, but if it needs to run when I overclock it while playing games, thats fine. My OS is windows XP if that matters.

So what kinda utils are out there that will do what I'm looking to do?

Thanks guys!!