[Ham-Mac] Mac for Ham use

[Cecil Bayona]

I have several Mac's running 10.2.6, a 8600 with a G4 800Mhz CPU, a G3 
beige desktop with a G4 400 Mhz CPU and I have a Blue and White G3 with 400 
MHz G4  CPU.

My question is which one is more compatible for running ham software, for 
decoding PSK31, RTTY...etc.

I'm leaning  towards using the G3 Beige Desktop because it's nice and 
small, but I'm not familiar with Mac ham software and their requirements, 
would any of these have problems running  software to decode the audio from 
the radios?

Thanks for your advise

Cecil Bayona