Newbie Question: 64Bit Processors?

[dumdum8684]

Uhhh.... not quite.

The reason nobody can write code for the Itanium is because there are no good optimizing compilers out there that can do the neccesary code scheduling to take advantage of the VLIW architecture that the Itanium uses.

The 48 bit thing you are referring to I believe is actually 40 bit, and that refers to how much physical memory a processor can address. 2^64 can address an impossibly large amount of data. In fact, I read once that this can address more memory addresses than there are particles in the universe, or some such unbelievable number.

The 64-bit thing actually comes into play in that they actually CAN accept 64 bit instructions. That means MUCH larger data types (32 bit integers, etc) can be moved into the CPU much faster or in parallel.

If you read any of the a+ study guides they talk about the old intel chips...the address bits is different than the memory accessing bits. and the reason the itaniums didn't take off is that they weren't backwords compatable like the AMD is.

 

[dumdum8684]

lol, 64bit isnt the majority ATM, i dont think we are ready for 128 bit for a long while.

The 128 won't be a PC chip...it will be for their AS/400 systems

 

[TheHeadFL]

If you read any of the a+ study guides they talk about the old intel chips...the address bits is different than the memory accessing bits. and the reason the itaniums didn't take off is that they weren't backwords compatable like the AMD is.

I don't think you read the part about my saying that the Itanium is based off of a very esoteric VLIW architecture. Itanium is not even close to "just" not backwards compatible. It has NOTHING to do with x86. It isn't even close.

 

[TheHeadFL]

EM64T? Why aren't they advertising it?

If you don't believe me, then look up on intel.com or any number of retailers. EM64T is just x86-64 except released by Intel.

 

[TheHeadFL]

The Itanium 2 was a piece of crap.

Not if you wanted to use it for a supercomputer to execute hand tuned assembly code. There are currently no good optimized compilers for it. (There may never be, due to the difficulty, though)

Intel says it plans to continue supporting it.

 

[dumdum8684]

If you don't believe me, then look up on intel.com or any number of retailers. EM64T is just x86-64 except released by Intel.

I wasn't discrediting you...I was wondering what it stood for and why they weren't promoting it? Just a question I believe you.

-Aaron