Having troubles @ 66Mhz

[dude]

I bought a new system in the summer of 2000 it was a Celeron 333@ 500. Recently I bought a celeron 733 and tried to just run it a normal bus speed of 66Mhz. I changed to FSB to 66 and turned off the computer then switched chip's. I turned it on and no video and no warning beeps. So I cleared the bios and the same thing. So I went back to my cel333 and it started fine but the FSB was back at 100. I changed it to 66 and I got the same results that I did with the cel733. So I go to supermicro's page and they say that I might not have video after I go down to 66Mhz and just clear the bios no problem. But every time I clear the bios it goes back to 100fsb!! So I e-mail them they say that it could be the slot 1 to 370-pin adapter I'm using maybe it cannot support 66Mhz FSB. Ok so I e-mail them the type of adapter card I'm using and they say it is not dependant on the type of adapter it is dependant on the motherboard's ability to support 66Mhz fsb! My setup is a Supermicro PIIISCD with a SuperMicro CL2S1 adapter card. Can anyone help me I'm completely stumped?