If you use regular desktop hard drives, it may work but down the road your raid array may corrupt and cause data loss. So save yourself some trouble and get Raid rated hard drives. Don't go cheap on your data.
Some desktop hard drives are rated only for Raid 0 and 1
For example Western Digital:
http://www.wdc.com/wdproducts/library/S ... 701229.pdf
" Desktop / Consumer RAID Environments - WD Caviar Green Hard Drives are tested and recommended for use in consumer-type RAID applications
(RAID-0 /RAID-1)."
http://www.wdc.com/wdproducts/library/S ... 701277.pdf
"Desktop / Consumer RAID Environments - WD Caviar Blue Hard Drives are tested and recommended for use in consumer-type RAID applications
(RAID-0 /RAID-1)."
http://www.wdc.com/wdproducts/library/S ... 701276.pdf
"Desktop / Consumer RAID Environments - WD Caviar Black Hard Drives are tested and recommended for use in consumer-type RAID applications
(RAID-0 /RAID-1)."
**** Now that WD came out with the Red model, WD remove all the above sentence and changed to this
http://www.wdc.com/wdproducts/library/S ... 771438.pdf
WD Green hard drives are tested and recommended for use as secondary storage in PCs, external enclosures and applications that require cool and
quiet operation. Desktop drives are not recommended for use in RAID environments. Please consider using WD Red™ hard drives for home and small office 1-5 bay
NAS systems and WD enterprise hard drives for rackmount and NAS systems with more than 5 bays.*
http://www.wdc.com/wdproducts/library/S ... 771434.pdf
WD Black hard drives are tested and recommended for use in PCs and high-performance workstations. Desktop drives are not recommended for use in RAID
environments. Please consider using WD Red™ hard drives for home and small office 1-5 bay NAS systems and WD enterprise hard drives for rackmount and
NAS systems with more than 5 bays.*
*WD hard drives are designed and tested for