Hi, I figured it out: The problem was that during the boot process the SATA controllers are initiated after the array building. The IDE controllers are initiated earlier, that's why the RAID1 with the IDE drives worked... So I did a "lsmod | grep sata" and filled in the sata module names to the /etc/modules. After a reboot the SATA RAID5 was up and running !!! Best regards, Stephan