OT 2.4 ghz P4 running at 1.9 ghz

Got a new 2.4 ghz pent 4 to function as a Linux Terminal Server (LTSP -
RH8). When I boot it, it claims to be running at 1.9 ghz.

The setup (press delete while booting) screen that is supposed to allow me
to set the CPU speed seems to be "locked" (won't allow any changes to that
screen) and does not show the set CPU speed option.

Any ideas.