Platforms and performance

Hi!

I'm concidering Postgres instead of for example Oracle or DB2. Can anyone
tell me what platforms Postgres runs on?

* Alpha (True64)
* Sparc (Solaris)
* PowerPc (AIX)
* IA-64 (HP-UX)

What kind of performance can one expect from Postgres? Can I upload the
database into memory and run without disk-access for higher performance?

How easy is it to hire someone to help? We're based in Gothenburg, Sweden.

/Roger