I have an ECS P35T MB and I have OC'd the E2180 to 2345 ok but over that and the BIOS complains about a 200mHZ CPU not being supported. Also when using CPU-Z 145 I see the CPU is jumping between 1371 and 2290. The Stepping rate also changes from 6x to 10x. Is this normal? In past CPU's the OC rate stays consistant. What do other users see when checking performance?
The frequency is jumping because you have Speedstep turned on in the BIOS, a feature designed to lower a CPU's power consumption when not in use.