Core clock speed
From TheBestCaseScenario
| Core Clock Speed | Processor speed |
The Core Clock Speed is the overall speed that the CPU is running at, after multiplying the FSB and Multiplier together.
This is how you can compare against other CPUs. Example: A Intel Q6600 runs at a clock speed of 2.4GHz at stock, if the FSB is increased from 266MHz to 300MHz the CPU can run at 2.7GHz overall, this would make the overclocked model faster.
Overclocking allows you to match the Core Speed of higher and more expensive models and get performance increase at no extra cost.