Hi Andreas.

> You may ask how much of a difference this really makes. Well, how about
> this: I very recently switched to gcc for compiling the Windows VM. 

There is also PGCC, a GCC compiler targeted specifically for Pentium
processors... it has been useful in emulation projects such as MAME, 
and there was a guy that offered the PGCC compiled version instead of 
the regular GCC one. The PGCC version usually was at least 10% faster. 

I do not know much about C compilers neither GCC or
PGCC in particular, but perhaps this can be useful...

Andres.