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Six hard drives in a RAID array: It sounds like it would be noisy, clunky, and hot. But as JMR's new SATAStor shows, a RAID array can be compact and quiet.
Imagine a six-drive array of 80GB hard drives that fits entirely in a single 5.25-inch, 1/2 height drive bay. This is made possible by using 2.5-inch drives primarily targeted for laptop systems. We originally saw this JMR SATAStor at the Intel Developer Forum a year ago.
Of course, you can't just drop a six-drive array of SATA (Serial ATA) drives into your typical desktop system and expect it to work. So 3Ware shipped us an Escalade 9500S-12. This PCI-based RAID controller supports up to twelve SATA drives in a variety of RAID configurations (and in a JBOD—"just a bunch of drives" setup, if that's what you want). The controller offers flexible support for RAID 0, 1, 10, 5 and 50, giving you a choice for the right mix of performance and data integrity.
If you're thinking that the combination of the Escalade and six-drive array isn't really a great fit for a desktop PC, then your guess is correct. It's really well-suited to small servers that need to be compact and exist in low-noise environments. Alternatively, it could be used in a workstation for video or audio editing.
We're going to plow right ahead and test it in a standard desktop system anyway—partly just to show we can do it, and partly to see how it compares with internal SATA arrays. We stuck with just a RAID 0 configuration for this article, but we'll be investigating performance in other configurations in the future. This particular hardware setup is somewhat hobbled by the use of 32-bit PCI slots, though the Escalade 9500S is a fully PCI-X-compliant part. It can run in a 32-bit environment, but its real comfort zone is in a system with a 64-bit PCI-X subsystem. The majority of desktop PCs, of course, lack PCI-X capability (not to be confused with PCI Express, which is a completely different beast). At one point, Gigabyte was offering a variant of their 8KNXP motherboard, the GA-8KNXP Ultra 64, with an Intel 875P chip set and a pair of PCI-X slots. But trying to locate one of these is an exercise in frustration. Another possibility is the SuperMicro P4SCT, which seems to be readily available. Both are socket 478 solutions, though, and don't support more recent LGA775 processors.
Alternatively, you could always go for a workstation configuration. A variety of socket 603 (Xeon) and socket 940 (Opteron/socket 940 Athlon 64 FX series) motherboards are available. They're typically pricier (and often larger) than normal ATX boards, which means you'll need a workstation-class chassis.
But we digress. The Escalade controller does work in a 32-bit PCI slot, so we popped it into our storage test bed and took the SATAStor for a spin.