Why are you comparing products with 2½ years apart?
Because the following were being mentioned, and their performance compared:
1. The Pentium 4, which stopped speeding up about 2006.
2. The Pentium-M, which also stopped speeding up about that time.
3. The Core 2, which stopped speeding up about 2 years later than that.
Therefore, Either release P4 v. release C2D, or mature P4 v. mature C2D, were the most fair options, since no P-M was there to choose.
That would be around 4 years, and nowhere was IB being mentioned, so no, it would not at all be the same. I did not include any P-M bench, because I found none there.
The problem is here you need a tech thats 3-5 times faster than the old one to innovate. Else we are stuck in the past. x64 was most likely made on a napkin at lunch. And a true example on the risk vs reward factor issue with competition.
A favorite quote of mine, by Felix von Leitner:
"If you cant explain it on a beer coaster, its too complex."
If it can be made on a napkin, and other engineers gotten behind it, that doesn't sound bad at all. I'll take that over a pie in the sky any day.
Yet, I would very much disagree with your claim about needing 3-5x faster to innovate. To innovate, you need something different that people will want to buy. There's plenty of evidence that processors not faster have managed to do that quite well, by having other useful properties others don't, such as cost, and ease of integration with otherwise custom hardware.
To be 3-5x faster, you've got to figure out how to get there, and right now, nobody has a way that works. IA64's didn't, and other predicating schemes don't even seem to simulate well enough to catch on (wish branches probably being the most promising, as of late). Nobody has yet figured out a magic ILP pill for CPUs, short of all RAM being on-die or on-package SRAM. Plenty of work has gone into it, and we have gotten better compilers, better CPUs, and working transactional memory, for some of that trouble, but no massive performance boost.
x86-64 got rid of the worst legacy crap, then took all the good things x86 has, and didn't screw them up. IA64 threw out all the good (code density, efficient immediates, nice MMU/PTE setup,
not relying on profiled builds for decent performance, etc.), and didn't add anything good itself other than short pipelines (part of what made it a nice number cruncher), and some super duper RAS (to help kill off competition, which worked), while taking RISC to a silly extreme.
ATM, performance is very much limited by R&D. We're close enough to the physical limits that no one without hundreds of millions of dollars to put into it, will be able to come close to what Intel has pulled off with x86. Even as it gets slightly better per SDRAM generation, slow memory alone is enough to create a massive barrier to entry, even before any patent concerns start to crop up. When silicon finally gets replaced, maybe we'll see some real shaking up. Until then, no fancy shmancy ISA is going to do more than get a generation or so's worth of performance benefit over another, and even that will require time and money similar to what was put in to that 'other' one's processors.
So they are turtle slow in increase.
Stop changing goalposts.
An increase, by its very definition, is relative, not absolute. x86 hasn't increased in performance as much as ARM is now since the late 90s. Nearly doubling performance for multiple generations, with only a couple years between them, is not a slow increase in performance. We haven't seen that in our desktops or servers for over 12 years, now.