Crucial 512mb pc2700 ram

[dynasty]

I upgraded from an AMD 2500+, ASUS A7N8X Deluxe mobo. I upgraded to a P4 2.6C, ASUS P4P800. My computer won't beep on and I know it is because my ram can't run at the default 400mhz fsb. I need to turn it down to 333mhz for the computer to bootup. How can I lower it, if my computer won't bootup? Thanks

 

[Kroffty]

Try restting the cmos jumper?

I have the same ram and its running right now at 400mhz by spd in the bios.
Maybe try changing the slot the ram is in.