Alright, I just thought of something. I know it's an old thread, but I may have found a solution nonetheless. In my BIOS, after I clear the CMOS, and it sets everything back to it's default settings, It has the FSB for the processor listed as "100 MHz" and I have to set it back up to "166 MHz" to get it to run at the speed it's supposed to. Maybe in your BIOS it has the FSB set to 100 (or whatever your BIOS' default FSB setting may be) and all you need to do is tell it that it's a 200 MHz FSB (which is what you should be running at with that processor).