As an example, back in the days the Q6600 came in G0 and B3 steppings, despite being the same model CPU - and they had differences
I understand that. And I am not disputing or questioning that. I am just saying that if one is G0 and the other is B3, then clearly they were NOT "identical"! They were very similar, and certainly in the same family, but they were not identical.
If the user did his or her homework - as they should - and thoroughly researched the data, they would have easily seen the difference. And for sure, if someone is building a dual-processor system, they likely are not total noobs - but if they are and don't know enough (or are too egotistical) to research and do their homework first, then they have no business working this project, IMO.
This is nothing new or unique to processors either. For example, when a controller board dies on a hard drive, you cannot just replace the board from any drive from the same maker and model number and expect the drive to work. You have to ensure the revision number is the same too. Or else, you might get a newer one from Taiwan when you really need the older revision that came from Malaysia. Exact same model numbers but NOT "identical".
When looking to flash the BIOS on a motherboard, ensuring the same model number is not good enough. You must ensure you have the right motherboard revision number too. Same model, but not identical.
Steppings matter! Always have.
^^^THIS^^^ And I believe anyone who has built a dual (or quad) processor system should already understand two (or four) processors with the same model number may not be identical.
Way WAY back in the day I was supporting hardware in a major software development company for a big DoD secure network. We were building new quad-core servers with Supermicro boards. We not only had to ensure the processors had the "identical" stepping number, we made sure each set came from the same manufacturing "Lot" number too. Fortunately, these days, motherboards are much more tolerant to slight differences, and processor manufacturers are much better at ensuring consistency and compliance to specs. So ensuring the same lot number is not necessary.
Again, I am just saying, identical means identical - not "almost" the same. And maybe I'm totally wrong, but it is my experience that anyone with experience in this area already knows that. And if new to this area (either professionally or as a hobby enthusiasts), they should know to do the research before spending their $$$, or committing someone else's $$$. That was drilled into me when I first started building dual and quad processor systems. And I drilled that into the junior techs when they started building them.
So back to my original question - isn't it implied that "identical" means the same stepping number too? It does to me.