CPU Speed?

[NeoReloaded]

"If you are looking for the ultimate INTEL box then look no further than the Ultima OC 8800 GTX Intel Core 2 DUO E6600 Dual Core overclocked beyond X6800 clock speeds"

That is quoted in the description of the pc that i brought but how do i actually check the CPU speed to make sure? Yes i am still a n00b

Thanks