Hi, > (1) A SATA HD for opterating system; > (2) A small but fast SCSI HD (~20-40G) for data processing; Just to say, that my guess would be that disk speed would not be a large factor in SPM processing times, because even NFS over a 100Mb link only had a minor effect compared to local hard disk: http://www.mrc-cbu.cam.ac.uk/Imaging/Common/spm_benchmarks.shtml I would be very interested to hear of any other data that people have on this issue, Best, Matthew