How can you detect on runtime if your sql-server 2005 instance is a 32 or 64 bit instance?

How can you detect if your sql-server 2005 instance is a 32 or 64 bit instance from C# code? If you know some documentation on this issue, please let me know.. Thanks!

From stackoverflow

• I'm curious... why?

  E. : Optimizations fine tuning..

• Use SERVERPROPERTY ( propertyname )

  With property name Edition.

  64-bit versions of the Database Engine append (64-bit) to the version.

  SELECT SERVERPROPERTY ( 'Edition' )
  

  For me on my x64 machine returns the following string value: Enterprise Edition (64-bit)

  You could also check the env variable PROCESSOR_ARCHITECTURE to see what the machine itself is running as.

  E. : Is this listed also on the registry or can be concluded from a file version? I need a way to do this not assuming I have a valid connection.

  Brian R. Bondy : updated answer with PROCESSOR_ARCHITECTURE note. I'm not 100% sure if you can install an x86 SQL on an x64 though. But I don't think you can.