Re: 2.4C/3.0C
From what I recall there was so much demand for the 2.4C that there were claims that Intel was taking chips that were earmarked to be 3.0Cs and setting the multiplier to 2.4C (in order to have enough chips to fill the demand). Enthusiasts would get ahold of those 2.4C chips (that were really 3.0C), and set the multiplier to 16x. Faithfully we'd read thread after thread stating 'ZMOG the 2.4C is a legendary overclocker!!!!!11' when in reality you squeezed 200 MHz out of it...
AMD will never own up to it, but I'm sure the same was true with the Barton 2500+ XPs vs 3200+ XPs. I never actually heard of anybody who owned a Barton 2500+ that could NOT run it at 3200+...which leads me to believe they were all 3200+ chips, it's just that some of them came in 2500+ boxes...
That was the rumor about the 2.4C, but no one really knows for sure outside of Intel. I don't recall that ever being substantiated. That said, I have actually seen a 2.4C that wouldn't do more than 2.7GHz or so. I've also seen a 1.8GHz Celery hit 3.2GHz. It was one of the gimped cache socket 478 chips so it was still slow as hell, but the clocks were insane. You might be right on the Bartons as well. I don't know for certain. Using the 2.4C and 2500+ as examples, I wouldn't be surprised if what you are saying has some truth to it. It only makes sense for Intel and AMD to fill the orders they are getting. If more people are buying mid-range CPUs than high end ones and their yields are good enough to make high end chips out of all of them, it's the sensible thing since their costs on manufacturring for a 2.4C or XP 2500+ are the same as making a 3.0C or XP 3200+.