As Always: Choose Your CPU Carefully
The 3.0 GHz P4 (FSB800) is designed for a core voltage of 1.550 V. A general rule is that the signal quality within the CPU deteriorates as speed is increased. To allow the processor to run at higher speeds, the switching characteristics of the transistors can be improved by increasing the voltage in steps. This does mean, however, that some transistors will thus operate beyond their specification, which will reduce their life expectancy. Moreover, increasing the voltage increases power consumption and increases power dissipation by the power of two. You will see the effect of this right away; the processor will become very hot and will require a more effective method of cooling.
Some seasoned overclockers are aware that significantly increasing the core voltage provides the best conditions for overclocking. But our experience in the THG labs has shown that what is needed is an optimum relationship between core voltage (and the consequent power consumption and dissipation) and CPU speed, assuming that adequate cooling can be provided. This observation only applies to extreme overclocks of 30 percent and more using top-of-the-line P4 models, because a 2.4 GHz processor is a completely different animal than a P4 CPU that has already been clocked higher at the factory.
In the lab we have not achieved any improvements in stability by increasing the core voltage beyond 1.65 V.