2 x 2GHz & 6 x 1.7GHz
4 x 2GHz & 4 x 1.8GHz
The CPU speed indicates how many processing cycles per second can be executed by a CPU, considering all of its cores (processing units). It is calculated by adding the clock rates of each core or, in the case of multi-core processors employing different microarchitectures, of each group of cores.
CPU speed: is this important to you?