As chips come off the line, they're tested. They test for 3.2GHz until they fill that queue, then test for 3.0GHz, 2.80GHz, etc.
The problem with that theory is you assume they are all going to run at 3.2. What happens to a whole wafer that only runs at 1.8? These people are in business to make money and they will not provide any more quality than the market will pay for.
You may, in fact, be getting a chip that was never tested at the higher clock rate or you may be getting one that failed at the higher clock rate.
I guess the real question is whether that extra speed actually translates into any real time savings in your day. In any virtual memory machine, as soon as your total loaded applications exceeds your RAM you are running at the speed of your disk drive. Most windoze machines do that by the time they boot to the desk top unless you have a buttload of RAM.
