Ga-7zx (Rev 5.0) Multiplier

How do i lower the multiplier on my Mobo? i dont see anything for it in the BIOS. there are switches on the mobo that let me change the FSB from 100 to 133. I can get my 800MHz Duron up to 880MHz, but it's unstable past that. Someone told me to lower the multiplier and see if i can raise the FSB higher, but i dunno how to lower the multiplier?? also, how do u OC PC-133 memory?? I read the tutorial, maybe i missed something

Do a search for "pencil trick" i think that the duron can be unlocked like that..