The idea is that giving a CPU more voltage will increase the stability of the CPU at a higher frequency. So, you start out by tweaking the multiplier and FSB. Go up in small increments at default voltage. Once you encounter instability, up the voltage a bit and repeat the process. I try not to go over +.2 volts. Figure out what gives you the most bang for your buck. On my CPU, I can get 1050 at 1.85 volts, or stick with 959 at 1.75 volts. A gigahertz is neat, but not worth upping the voltage that high. Increasing voltage increases heat produced and shortens the lifespan of your CPU.