Sorry for the lack of details:

In the mac IIcx:

The 8gb drive spin up, is visible as a disk, is partitionnable, is installable and bootable. (everything works).

In the SE/30:

At boot, the 8gb drive spin up, made clicking noises for 0.2 seconds (and then stops clicking), then it is never detected by the system (SCSI tools reports no device, Apple SC disk utility says no disk, etc).

I tried with another scsi disks in the se/30, they are never detected, but spin up.

The only drive detected and partitionnable, installable and bootable in the SE/30 is the 20mb MiniScribe disk.