From Blackmagics press release
‘Blackmagic Design’s testing has shown, that when the new Apple Mac Pro is populated with 3 x 500 MB SATA disks internally mounted and striped with RAID 0 configuration, approximately 170 MB/sec disk array performance was achieved. This allows customers to build lower cost HD disk arrays for simple capture and playback tasks. For higher performance editing solutions, Blackmagic Design’s testing has shown Apple’s Xserve RAID works well as a high performance uncompressed HDTV disk array. ‘
I guess It would be nice to put the system disk in the spare optical slot then have a 4 internal way raid