Had a similar problem with CSPPC and a WD LVD SCSI drive. I had to set the drive to SE mode, no U160 because it wasn't communicating properly with the CSPPC SCSI ( HDToolbox would lock up ).
With 8 bit SCSI devices on the bus, I had to set the CSPPC boot menu settings to 8 bit.
With newer drives and old controllers, it seems that there can be some scsi negotiation issues. Of course you also need to ensure that termination and cable lengths are proper.