Check out:
http://www.jbiscientific.com/Instruments/MassSpec/DE/Voyager-DE.html
You can purchase a new windows XP computer for a Voyager DE or used windows 2K computers are available. JBI Scientific stocks all the necessary ISA/PCI cards (Acqiris digitizer, Signatech Digitizer, 48 Bit I/O, Stepper Motor PCA, Joy Stick, etc.