Don't know much about your mobo, but I am running a P3-450 on an Asus p3v4x.
FSB is 124, for a CPU speed of 567mhz. I have the retail fan and sink on the CPU, but have two case fans (1 out in rear, 1 in in front) and a Card Cooler XT cooling things down.
Am absolutely stable, if still a bit warm. CPU runs 38 deg C at idle, about 134 deg C under stress.
Good luck