Ya that's how I OC my CPU too. If you leave all the c states and intel speedstep active in bios, it will only use as much CPU power as needed. It will range between 1.6 and 4.2. I find in older games it won't ramp up past stock speeds. Great for cool gaming and less power drain.
I find most optical switchers cheap and worrisome that some plastic hunk of poop is not reflecting the light properly. Let me know if you find a link for a good one.