manofchalk is correct. Though i would just add that turbo speeds are not sustained for prolonged periods to ensure long cpu life.
for e.g. i have a core i5 2400 cpu. It is rated to run at 3.1 GHz. However, if I am performing too many tasks at the same time, Intel turbo boost will increase the cpu speed on one core (its a quad-core cpu) to 3.4 GHz. This speed is sustained for only 1 second through BIOS default.
In that 1 second speed burst though, the processor completes far many things. Also, turbo boost becomes slower as more cores are involved. Different programs can use different number of cores depending on their coding.
for my processor, single core turbo - 3.4
2 core - 3.3, 3 cores - 3.3 and 4 cores is 3.2 GHz maximum
so a heavy program which can use only one core will see maximum turbo speed of 3.4GHz and another which can use all for cores will see maximum turbo of 3.2 GHZ
it's a lengthy explanation but is probably what you were looking for