Vista - diff between X64 and IA64

just downloading windows XP professional X64 from MSDN but it only give the option for win XP pro X64 but in the product keys it have two option one is X64 and one is IA64.
so is there a diff software that i have to download and i am not able to locate in MSDN or its just that i only need diff product key when i install it on ITANIUM system and diff product when install it on normal X64 system.

and apologize admin to post a XP question in here need to get the confusion out.

The IA version is for Itanium intel prosessors. I doubt you have one. Get the regular and you'll be fine.

What is an Itanium processor Joel? LOL I googled it and got the intel definition including the following: "Itanium-based servers are incredibly scalable, allowing configuration in systems of as many as 512 processors and a full petabyte (1024TB) of RAM." But can you translate that into dumbbuttaneese so I cqan understand it lol? Here I am proud of 8 GB's of RAM and they are talking a petabyte? LOL Vista had a cow with 8 gigs, how is it gonna run that much? 512 processors? Do they work together? What are they solving? The answer to life and everything in it/ I mean we already know the answer to that is 43...........

OK - What we know of (on the consumer side) as x64 is the old set of x86 (32bit) instructions which have been extended out to 64 bits. If you are a 'regular' computer user (like nearly all of us), then this is what you need.

IA64 is a 'pure' 64 bit architecture, designed from the ground up for heavy duty server environments. It is dramatically different and not compatible at all with x86/x64.


{edit} The answer is 42, actually. But not really, if you go on to read the other books. Of course, you can't know the answer and the question at the same time, so...

IA64 is the name Intel used instead of EMT64 for 64bit since its licenced from AMD?

IA 64 is Intel's baby, and was aimed server side from start to finish.

As you stated: AMD-64(X86-64) is what AMD created as a superset of the 32 bit x86 instructions. Since it is/was backwards compatible, AMD won the 64 bit battle: Microsoft's support of this was the Big Fat Domino that knocked Intel's not~backwards~compatible "EMT-64" out of the ring. EMT64 was later dropped, Intel conceded the point and adopted their own version of what AMD created. The 'common' name for this on the Intel side is x64.

Wow....do you think this rig could play Crysis at full speed?

r2rX