X-bit labs decided to check out RAID0, RAID5 and RAID10 arrays made out of four HDDs. Here are the HDD models they tested on the Areca ARC1220 controller: Hitachi Deskstar 7K400 (HDS724040KLAT80), Maxtor DiamondMax 11 (6H400F0), Seagate NL35 (ST3400832NS), WD Caviar SE (WD4000KD), WD Caviar SE16 (WD4000KS), WD Caviar RE (WD4000YR). This list includes two 'professional' drives from Seagate and Western Digital (ST3400832NS and WD4000YR) and four ordinary 'desktop' drives. To build the arrays they used four samples of the same HDD model, from the same batch and with the same firmware version.

First, 'professional' hard disk drives haven't showed any great advantages over 'desktop' HDDs in terms of performance. I didn't benchmark the drives under vibration, but anyway...Second, you could see the "benefits" from the support for NCQ technology. I mean in tests that emulate server-like operation modes of the disk subsystem. Third, despite the declared support for NCQ by the drives from Seagate and Maxtor, it was the drive that doesn't officially support it that really utilized that technology to a positive effect. The NCQ support in Seagate's and Maxtor's drives is a topic for a separate investigation.

Fourth, the Hitachi drive benefited from having five platters in one test only: when I deliberately narrowed the test's operating zone. Otherwise, this HDD would lose either because or its low areal density or because or its small cache buffer. So, I wish I could test the T7K500 model, too. Fifth, I recommend you to take notice of the WD drives. The company has made a real breakthrough with its xxxxKS models!