Server upgrade recommendations

[Peter Payne]

Hi, I am interested in the possibility of moving my Intel Filemaker  
Server 9 machine from a 2 ghz PPC to whatever the best Intel box would  
be, most likely a 2.66 Mac Pro that I have here at work. I'd like to  
ask if anyone could tell me a) what the likely overall database speed  
increase is likely to be, and b) does FM Server specifically use  
multiple cores? I dislike the idea that my expensive multi-core Mac  
might not be benefiting from multiple cores, and I can't find any  
information specifically saying that it does work well with modern  
Macs. Can anyone give their two cents and help me figure out if  
upgrading to an Intel machine for the server will really help my  
overall serving speed on the user end?