More Details Emerge on AMD's Hammer

Diabolus writes "Anandtech have more information on AMD's upcoming Hammer processors. " Talking with several engineers who are in the know about it, the Hammer looks pretty frickin' amazing. Itanium will have a run for its money, I suspect.

Comments

Itanium, etc.

[ackthpt]

While the thought of Itanium duking it out with Hammer may encourage visions of one company stomping another, plus heated discussions, flame wars, and so on, my interest has always of having a 64bit desktop. Intel some time back indicated that the Itanium was targetted exclusively at the server market, is likely rethinking that point. Perhaps McKinley (the joint project with HP) is Intel's idea of the post P4 desktop processor, as I've seen elsewhere that Itanium's x86 emulation makes a PIII look attractive.

The ability to build a desktop workstation with the ability to run all my old x86 crap, fast, and move into 64bit software, also fast, is highly attractive. Athlon or P4 will undoubtably be the choices for the next year, but when AMD gets the Hammer out into the mainstream with a mainstream price, Intel watch out.

Lastly, Microsoft, last I read, didn't indicate any interest in doing a version of XP for the Hammer. Perhaps that hasn't changed. If not, there's a potential hole through which someone may exploit Microsoft's disinterest. Linux, sure, AOL, Hmmm, you know that's a mean fight going on between Reston, VA and Redmond, WA, if the Hammer is attractive to home users, don't be surprise if AOL chooses to support it. It's entertaining to think about, anyway, however you feel about the combatants.

Re:Itanium, etc.

[maraist]

I thought McKinley was just the .13 micron version of Itanium, perhaps with more cache. Does it have an enhanced ability to do IA32?

McKinley is a whole mess of add-ons.. Not least of which is the idea that it can issue more EPIC instruction / clock than the Itanium. The original idea was that Itanium would chapion the instruction set, but would be an unwieldy beast with all it's new features.. But it would be enough to transition the market place (too bad it's practical performance sucked). McKinley would then be the knock-out punch that fully utilized it's potential (though at greater cost due to increased numbers of components). From this Itanium would be a low end that allowed "entry-level servers". Then they'd have time to go redesign new features for their next [incremental] generation... Their EPIC instruction set has templates so that adding whole new classes of functionality "should" be trivial.

Course I don't think they expected having to relegate Itanium as a "pilot" CPU with embarrasingly low frequency ratings (but MHZ is all that matters, right Intel?). Doesn't sound like the P4 guys are under the same marketing department as the Itanium guys (GM in the making?)

-Michael

Re:Backwards compatability big advantage

[stripes]

The trick, naturally, is to design a proper instruction set to begin with. Then you can extend and enhance it easily without having to break backward compatibility. Too bad Intel didn't realize that.

The SPARC and many other RISCs had a "seamless" 32 -> 64 bit transition mostly by doing two things.

1. They added 64bit load and 64 bit store instructions (existing load and store remained 32 bits). All the other stuff (register to register instructions) went to 64 bits.
2. Made large (incompatible!) changes to the supervisor mode. This only matters to the OS and boot loader, and Sun owned the dominant OS on the SPARC boxes, SGI owned the dominant OS on the MIPS boxes, and they made all the changes to the OS as needed.

There is no reason Intel/AMD couldn't make new 64 bit load and store instructions, and redefine all references to EBX (and the other 3 registers) to be 64 bits. That would work just fine.

The part that would suck is Intel and AMD do not own the OS, or even the bootloaders that runs on their CPUs! MS, and a handful of BIOS makers do. They would have to be convinced it is worth it to do anything.

NOTE: I'm not saying the x86 instruction set is anything close to well designed. It is a shambling horror, but extending it to 64 bits is not really harder then extending the SPARC to 64 bits. In fact if you look at what AMD did it is a pretty easy change (and I think the article is wrong, you can use the new 4 GPRs without having to do any 64 bit stuff, but the OS still needs to be changed to save and load the extra registers).

Intel merely decided the 32 bit to 64 bit change seemed like a good time to try to make a play for the high end market, and to do that with a new instruction set. That might have even been a good idea if they hadn't screwed it up enough that the itanimum earned the nickname the itanic...