The 64 x86 thing . To compare itanic to a 64bit x86 after the fact is way off the mark . Had hammer not happened Intel wouldn't be making X86 now . EPIC is were intel was heading . Doesn't BD now contain elements that went into itanic .
Tens of MB caches, massive binaries, piss poor peformance in code with tons of indirect branches straight out of a standard compiler, static scheduling, putting tons of their best and brightest on the porject in a final effort to make it profitable (successful), once it became obvious that compilers weren't there yet?
I don't see any of that in BD, or for that matter, any other modern general-purpose CPU. No doubt Itanium offers excellent R&D results, and has probably paid for itself in x86 developments, but from the ISA on up, it's not a good general-purpose CPU. The idea that hardware is inferior to software in terms of scheduling and prediction requires either (a) additional instructions doing speculation and on-CPU memory management running as part of every thread, and/or (b) assuming that unique inputs do not create unique outputs, regarding good branch prediction and memory fetching formulas and algorithms
(which would allow them to be added to IA64 CPUs, to provide a, "have your cake, and eat it too," result, if it weren't generally false).
It's not just 64-bit addressing, but that the Itanium would have needed to have much lower power consumption, and much lower cost, with no detriment to integer performance, for it to not fall flat as a mainstream CPU. The Itanium requires specific optimizations per application to perform decently, also, if you don't get lucky compiling it, which is not something mainstream developers will do. Some will be willing to have someone go in and take it from performing OK to performing great; but most need to be able give the code to something like GCC, MSVCC, etc., and use the result. The K8 took IA64's mainstream adoption from being a wasting disease to being smacked by a truck. Even w/o the K8, it still would not have happened.
EPIC might have been where Intel was heading, but the rest of the world wasn't. EPIC for certain tasks, like heavy duty number crunching, works pretty well. Most people don't do much of that
(at least, not at the cost of other workloads), and hardware scheduling and speculation still haven't reached their limits, by a long shot. IA64 for the mainstream was no more a good idea than a hundreds-of-watts 10GHz desktop CPU was. Intel was in its own little world, acting as though the wants and needs of computer buyers were irrelevant.