Itanium hardware is a lot better because its not bag down by the architectural requirement of X86.
Apples and Oranges...
Itanium is more of RISC(Reduce Instruction Set) type CPU and X86 is a CISC(Complex Instruction Set Computing)
Itanium can emulate x86 through software but it will be slower. Thats the reason Intel can't make Itanium x86 compatible. Intel will have to add more tansistors/circuitry to make Intanium x86 compatible.
RISC Type Processors:
Power PC (IBM , Freescale, PS3-Cel CPU designed by IBM)
SUN SPARC Processors
CISC TYPE Processors:
Xeon x86
Pentium Series X86
AMD X86
MCS 51/96 Micro-controllers
RISC Advantage
1) have fewer instruction sets
2) Run at a higher clock rate
3) Lower Transistor Count
4) Higher efficiency.... Multiple Instructions Execution per Clock Cycle.
5) Ist not bug down by the DEEP-INTRUCTION PIPELINE needed by CISC such as X86 Architecture.
Big Iron Machines for Scientific and design applications mostly use RISC. The LOS_ALAMOS labs that simulate nuclear explosion. Circuit Simulation & Synthesis that takes months to compute normally use RISC. These supercomputers have > 10K CPUs working together. Common software is UNIX/Linux Operating system, Design , Mathematical and Engineering softwares
CISC is mostly for office application, business, banking, games. CISC servers are cheap than RISC thats why its very popular and widely use. And of course MS-Windows, and MS-Office is probably 85% of the main application.