to use two or more 442modules will need a SysAxe Card - system accelerator (scsi controller who manager scsi disk for ProTools).
SysAxe must to be installed in to the fisrt slot and just "see" 2gb partition size
This setup works fine on quadra 950 and you will load up to 16 tracks !
compatibility:
ProTools software 3.2 w/ DAE/DSI version 2.95 and 2.96
cubase audio xt 3.x
digital performer 2.1
studio vision dsp 4.2.3
logic audio 2.5.3
I install ProTools "free" 3.4 w/ DAE/DSI 3.02 and works fine too ! then I pass thru this information to this site:
http://www.oakbog.com/PT3NuBus.html
obs: hook up the word clock ports !
wordclock out (first 442) to the workclock in (secund 442)
workclock out (second 422) to the workclock in (third 442)
word clok out (third 422) to the wordclock in of the last 442(fourth)
if you have difficulty to find a Sys AXe card to buy , contact me.
good luck!
Fabio