how to test the speed of i7 processor

You can perform a Benchmark with http://www.primatelabs.com/geekbench/

I am sure your processor is operating at exactly the speed the manufacturer rated it for.

But computer performance is based on many factors, including whether you have enough RAM for your simultaneous activities, and whether there is a "traffic jam" at your Hard Drive.

In some cases, apparent speed is influenced by bad Internet performance as well.