:?. o O (what is it your trying to do?)
If you want to run constantly at x8 @ 266, you will need to disable it. You would need to look for EIST and C1E settings in the bios.
Changing the FSB to 333 could cause stability problems since speed step will still try to change the settings to reduce power consumption, on that type of OC.
If your into OCing, try reading:Core2Duo Overclocking Guide