Next time I am reading the whole thread instead of just the op ;) But you are right, of course, in every point. So were I :)

@zarx im furthest from an expert. I have written 6 phases of the espesso compiler. Including code optimization. Built my own computer. And know a few data structures. So when I read your posts im able to learn something. Your details were a excellent read.

He did, and that wasn't a dig at zarx, it was very well put and respect to him for it.

But it's kinda obvious stuff really. Everyone here knows enough about developement that timing/expected target is critical for console gaming.

When games are "polished" ironing out frame rate issues are always going to be a part of that, changing architecture would simply remove all that consistency.  That is obvious.

This is no way confirmed but there is a quite well publicized rumour that the Sega Saturn had a 2nd CPU added late in the design process to try and improve the performance to match the Playstation 1. This might be why there was serious bottlenecks in the design with the shared bus of the CPU and also the various memory access limitations.

http://segaretro.org/Sega_Saturn_Development
http://en.wikipedia.org/wiki/Sega_Saturn

As stated by earlier posters, its highly unlikely to happen but hardware can and has been changed late in the design process before. The example of switching to a Intel CPU by the way would be impossible without a complete redesign, any changes would have to be of very similar architecture.

Yes, to some people it is clear as water :) But keep in mind this doesn't apply to all users here. Sometimes stating the obvious is useless but obviously prof's knowledge about technical things is so bad that he had to start this thread. I still wonder if there is more to it...

And the Saturn failed ;) Yes, Sega added the second sh-2 late to compete with psx which was the only thing they could do back then.

But nowadays I think Sony and MS were well-informed what the competitor was doing and it was clear very early both would go for a similar approach as no one wanted custom cpus again.

There are now two possibilities:

1. All current spec-rumors regarding Durango are mostly wrong. The specs we got came from an old dev-kit which MS in the meantime changed massive.

2. the current spec-rumors are true. Then MS has only a little chance to change crucial parts of the design. But keep in mind that we don't have the whole picture of the specs yet.

I just wanted to answer the OP's original query of whether there was any proof a console could or couldn't change its configuration.  I don't hold much faith in specifications of a console based off a early dev kit which in all likelyhood was a performance target and not completely representative of the finalized hardware.  I doubt the 21st May announcement will clear the specs confusion up though, that will be over the coming months as devs spill the beans once the NDA's expire.

Given how much is currently rumored and given that Sony actively talked about specs and let other devs talk about PS4 I think they will definitely say something to specs or do it like Sony via 3rd-party-devs.

But I think there are more important things they can tell us 21st. The NextBox will definitely be way better than 360 and will have comparable hardware to PS4 so this isn't really a matter to me.

I'm asking for proof, not conjecture.

I know all of these reasons already. I know that changing something like the CPU/GPU is a huge deal. I know there are contracts in place. I know this would result in massive delays. I know this would fuck with all the work developers have previously put into their games.

But is there PROOF?

Do we have a link or someone in the industry saying quite clearly "these contracts are all written long before production even begins", or "changing out a GPU for a completely different one would create massive problems, even 6 months out from release". I know the evidence, and I actually work with computers.

I don't think that is proof as much as it is confirmation. What's proofing is the process that would have to be undertaken in order to do it. We don't need and industry person to tell us that, they would have to tell us the miracle expection otherwise to make the topic not set in stone. Ultimately it would be expensive and time consuming, heavily delaying the console. It can be done but not in the same time frame. One thing we don't know is what exactly MS is using in their box. It could be an AMD APU like we have been leaked or that info could be entirely wrong and they never chose AMD or decided to switch a long time ago to launch this year. Or hell, they still are delayed and launching next year. It could happen.

I don't think you can just find industry people who will confirm this kind of stuff for the sake of confirming this stuff.

The most likely scenario is AMD and a 2013 launch though.