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Intel's Big Chip
DeadBugs writes "News.com has an article about the size of the upcoming revision for the Itanium. The "McKinley" chip will be 464 square millimeters which would make it one of the largest ever produced. Most of this is due to the 64 bit registers and 3MB of Level 3 Cache. There is also a link to an article about "Chivano" an Itanium which will include concepts from the Alpha architecture"
Just for some minor clarifications: The 464 mm squared is the area of the actual cpu die. Like the little square on top of an athlon. So 2 cm per side die is kind of huge for a processor. The actual processor out of the box would have to be much larger than previous models. Next, 3 MB cache sounds nice, but L3? It may be on die, but by that point the clock reduction probably makes it perform equivalently to a 256 k L1 cache, or a 512 or larger L2. Not that it won't help a lot for complicated instructions, and it's probably less expensive/difficult to engineer to hook a larger amount of cache to a slower pipeline than to add more cache deeper into the cpu's core. 64-bit cpu's will be important in the future, but only when compatible apps and OS designs become mainstream.
... if you can't run the apps.
Intel x86 is restricted to 48-bit addressing (with segment registers), and practically 64GB with modern OSes. (http://linux-mm.org/)
If I want more than 64GB of addressable physical memory (which I do for some apps), then who cares if you can give me a 32-bit x86 running at 900GHz, it's not going to do diddly squat for me, since _going over the PCI bus_ for swap is going to kill me vs a 1.6GHz 64-bit processor. And since you need to go over the PCI bus just to get to a pseudo-disk stuffed with RAM, that solution is still bogus.
I see your point that this isn't what Joe Blow's gonna put on his desk. But the improved address space is definately a big win, and that's assuming that they can't ramp up the clock speed in a hurry.