Is my system x86-based, x64-based, or Itanium-based?

You're using x86 based... because if you were using something else, you'd know it.

Basically, Itanium is a not very popular hardware platform - only HP and Unisys if I remember correctly even Make Itanium systems and home users don't have them - they are servers for high end systems.

If you're using XP, I don't know of ANY vendor who sold a computer WITH a 64bit version of XP.  Maybe there was one... but you'd again, you'd know it.  

If you don't believe me, look at your C:\ drive - if you are using a 64 bit version you'll see TWO program files directories - one that says Program Files (x86) and the other that says Program Files.

You're likely an X86. If you want to be sure, check out http://www.cpuid.com/cpuz.php

You should be able to do the following:

1. Open Command Prompt
2. Type set then enter.
You should get an output similar to the following:
ALLUSERSPROFILE=C:\Documents and Settings\All Users
APPDATA=C:\Documents and Settings\evano\Application Data
CLASSPATH=.;C:\Program Files (x86)\Java\j2re1.4.2_13\lib\ext\QTJava.zip
CommonProgramFiles=C:\Program Files\Common Files
CommonProgramFiles(x86)=C:\Program Files (x86)\Common Files
COMPUTERNAME=EVANXPS
ComSpec=C:\WINDOWS\system32\cmd.exe
DRSYSCFG=C:\DRS\Sys\Data\Drsys.ini
DRS_DRIVE=C:
DRS_LOCAL=C:
DRS_VERSION=Sys
FP_NO_HOST_CHECK=NO
HOMEDRIVE=C:
HOMEPATH=\Documents and Settings\evano
LOGONSERVER=\\CHHDNS
NUMBER_OF_PROCESSORS=2
OS=Windows_NT
Path=C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;"C:\Program Files (
x86)\Symantec\Norton Ghost 2003\";C:\Program Files (x86)\QuickTime\QTSystem\;C:\
Program Files (x86)\Common Files\ICPA\SQL Anywhere 10\win32;C:\Program Files (x8
6)\Common Files\Adobe\AGL
PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH
PROCESSOR_ARCHITECTURE=AMD64
PROCESSOR_IDENTIFIER=EM64T Family 15 Model 6 Stepping 4, GenuineIntel
PROCESSOR_LEVEL=15
PROCESSOR_REVISION=0604
ProgramFiles=C:\Program Files
ProgramFiles(x86)=C:\Program Files (x86)
PROMPT=$P$G
QTJAVA=C:\Program Files (x86)\Java\j2re1.4.2_13\lib\ext\QTJava.zip
SESSIONNAME=Console
STATION_ID=99
SystemDrive=C:
SystemRoot=C:\WINDOWS
TEMP=C:\DOCUME~1\evano\LOCALS~1\Temp
TMP=C:\DOCUME~1\evano\LOCALS~1\Temp
USERDNSDOMAIN=CUEROHOSPITAL.ORG
USERDOMAIN=CUEROHOSPITAL
USERNAME=evano
USERPROFILE=C:\Documents and Settings\evano
windir=C:\WINDOWS
Look at the PROCESSOR_IDENTIFIER, if it is equal to EM64T it is an intel x64 processor, if it is equal to AMD64, it is an AMD x64 processor. Itanium will list as IA64 I believe. All x86 processors will list x86.

Look at the PROCESSOR_IDENTIFIER, if it is equal to EM64T it is anintel x64 processor, if it is equal to AMD64, it is an AMD x64processor. Itanium will list as IA64 I believe. All x86 processors willlist x86.

I don't dispute the accuracy of this to identify the hardware capability - HOWEVER, in determining the version of Windows - this will only show it is or is not Itanium.  However, the Set command, as demonstrated, does show a Program Files (x86) - as I suggested would exist.

Evan, You're not in DC are you?

As in Washington, DC?  No I am in Texas.