You need optical outs, on the computers.
BTW,
If you are in the market for another computer, I would wait for the new Mac Intel Towers....(novemberish)
Maya recently sent me the stress test results of a MacBookPro, and they are insane...imagine how crazy the new Mac Towers will be.....
BTW here is the comparison...it is unbelievable. Note that the MacBookPro has a much higher polyphony count then the G5 QUAD!!!! wow.
Processor: 2 GHz Intel Core Duo (Mac Book Pro)
Ram: 2 GB DDR2 SDRAM
OS 10.4.6
Data storage: Firewire 400
Host application: Logic 7.2
Plugin: 1.0.5beta (INTEL)
Soundcard: built in Audio
Latency at 512 Samples (12ms) / 1.3 GB Ram usage)
Maximum Vienna Instrument instances: 32 (CPU load activity monitor 95%)
Maximum Samples loaded: ca.13.000
Maximum polyphony: 580 stereo voices
Processor: G5 PPC 4 x 2,5 GHz (Quad)
Ram: 4,5 GB
OS 10.4.5
Data storage: Firewire 400
Host application: Logic 7.2
Plugin: VI v.1.0.5.2
Soundcard: Digidesign HW (002)
Latency at 512 Samples (12 ms) RAM usage 2.54 GB
Maximum Vienna Instrument instances: 34 (CPU 95%)
Maximum Samples loaded: 24.530
Maximum polyphony: 476 stereo voices / (CPU 35 % Harddisk limit exceeded)