Consider using a hardware port multiplier solution instead of the software raid implementation of SATA controllers and port multipliers using Silicon Image chips. A 4x1 eSATA/USB Hardware Port Multiplier (HPM) that is OS independent and will work with any eSATA port is an alternative solution. The 4-port SATA integrated HPM with an Oxford OXUFS936QSE chipset uses hardware raid technology.
RAID mode selection is done using a rotary switch and setup is
completed by pressing a raid setting button. Once configured all is needed is to connect the HPM to your system via USB 2.0 or eSATA and detect, partition & mount the RAID volume.
RAID mode supported are FAST2 (2 drive RAID 0 Striping),, SAFE2 (RAID1 Mirroring), SAFE FAST (RAID 1+0 Mirrored Stripped), BIG 2 (2 drives Concatenation), FAST4 (4 drive RAID 0 Striping), BIG 4(4 drives Concatenation), RAID 1+0, RAID 5 over 4 drives, or RAID 5+S.
Connecting the HPM to onboard SATA ports on the motherboard is possible by using 2 eSATA ports PCI slot mounting bracket with two eSATA connectors to convert internal Serial ATA to
2TB, 3TB, 4TB, 6TB & 8TB Turnkey RAID solutions utilizing the 4x1 eSATA/USB Hardware Port Multiplier (HPM) are available at
The way software RAID works using SI controllers and port multipliers (PM) is that, you use mdadm to see and configure as a raid volume all 5 drives connected to the PM. If the PM is connected to non-PM aware controller card (legacy) it will only detect one drive out of the 5.
But using a Hardware Port Multiplier which uses an integrated hardware controller, the raid setup is done on the HPM itself. So once you connect it to a SATA port, it will be seen as a single RAID volume.