Historically, a statement like that would have meant that prices were low and you could move tons of volume...well, you or everybody just like you competing at the same basement price points. Even in 2003, investment analysis firm J.P. Morgan noted that the average sale price of desktop hard drives plummeted from $401 in 1992 to $77 in 2002—not a margin machine by any stretch of the imagination but great for volume. And to be sure, there's plenty of disk volume moving now. According to Gartner, hard drive shipment growth will exceed 20 % in both 2005 and 2006. By 2009, annual hard drive shipments will hit 650 million units.

Q2 2005 Overall Hard Drive Market Today's market is still very much based on 3.5" drive sales, but look for influence from 2.5" to become more dominant in coming quarters. (Source: Seagate)

But this opportunity isn't just about planting a drive in a desktop machine and sending it out the door. New interface formats, the rise of small form factor drives (2.5" and under), and an increasing tide of third-party external solutions have conjoined to make 2005 an incredible year for selling disk-based solutions. That said, there are still plenty of dollars waiting in volume sales comprised of low- to mid-range desktop drives for new systems.

"Much of commercial still wants a lowest common denominator type of drive, the single- and dual-head kinds of drives," says Jeff Burke, director of market research for Seagate. "Eighty gigabytes is still the sweet spot in the industry. Out of the 60 million 3.5" drives shipped last quarter, a good 80% to 90% were on one disk."

For those ready to look beyond the lowest common denominator, though, disk storage for the SMB market is a diverse, margin-rich landscape on which VARs and system builders can capitalize and build a thriving revenue stream into the future.

The SATA Scoop

Serial ATA is no longer the headline grabber it was when Seagate and Maxtor were pushing the first SATA drives into the channel back in the fall of 2002. The first motherboard chipsets supporting SATA arrived in 2003, and now in 2005 we're starting to see motherboards giving up a Parallel ATA connector in trade for more SATA ports. According to Silicon Image, a prominent supplier of SATA RAID controller chips, the market share split for SATA to PATA was 1.8% to 92.8% in 2003, 45.4% to 54.6% in 2004, and projected at 85.7% to 14.3% for 2005. In 2006, new PATA drives are forecast at only 3.4%, which is essentially a technological tombstone. IDC is slightly more generous, stretching PATA's lease on life out to 2008.

Q2 2005 3.5" Drive Market There are no surprises on the big four, but watch for Samsung to rise in the ranks. (Source: Seagate)

Aside from the superior performance scalability of SATA over PATA, the newer technology sports several other benefits over PATA. For starters, the drives are far more power efficient. Whereas PATA requires 5V, SATA only needs 250mV, and the newer technology offers two power saving modes: partial and slumber. SATA cables extend up to one meter (40 inches) versus PATA's 18 inches, are only 8mm wide for better system airflow, and are hot swappable. Because SATA is a point-to-point technology, you can only put one drive on each cable, but with smaller data connectors you can also fit more ports on a motherboard.

Serial ATA isn't perfect, though. In particular, the connector design needs improvement. We've now had at least two SATA drives cross our test bench and leave with snapped off data connectors, as in the male plastic L of the drive's data connector snapped off and stayed in the female connector of the data cable. This is no worse than the few occasions from years ago in which we've had PATA drive power connectors snap off and need resoldering, but, then again, we've never had a bent PATA pin that couldn't be straightened out carefully and made usable again. We suspect the SATA problem might stem from the strain put on the smaller connector when using both SATA data and power cables. In many cases, we've found that the connectors are slightly too wide to fit comfortably side-by-side on the drive's backplane and must be jimmied awkwardly into position. This is why we always prefer SATA drives that still retain the traditional four-wire Molex power connector.

SATA Ascending Research firm IDC gives PATA until 2008 before complete obsolescence. At present, SATA owns over half of the desktop drive market.

Ever since the 2002, drive vendors have been telling us that 3Gb/s speeds were on the SATA roadmap, just as 6Gb/s is still slated for 2007. Host bus adapter vendors, such as LSI Logic, sell 3Gb/s PCI adapters to accommodate the higher speed drives that are just now coming to market. Also, watch your motherboards. The new NVIDIA nForce4 Ultra and SLI chipsets support 3Gb/s SATA, as do Intel's 955X, 945P, and 945G chipsets. Older chipsets most likely will not support the new spec.

The other performance hot button in the new SATA extensions is native command queuing (NCQ). This is a carry-over from the SCSI and Fibre worlds that lets a drive intelligently sort commands for more efficient execution. This boosts performance and reduces drive wear. NCQ is ideally suited for transaction-heavy processing environments. There are little or no benefits when dealing with highly linear applications, such as video streaming, which have no need for command sorting.

"We believe that NCQ is an enterprise specification," says Sherri Besser, senior director, product marketing for Western Digital. "It makes no sense in desktops. In fact, in the benchmarks we've been running, NCQ hurts desktop benchmark performance, especially in sequential reads and writes."

New SATA drives can at last support true hot plugging so IT managers never have to power down a machine to exchange drives, and the new staggered spin-up feature lets users dictate how a group of SATA drives spin up so that they all don't rush online at once and create a massive power drain.

While all of these features erroneously fall under the "SATA II" moniker, it's important to know that drive manufacturers are free to implement all, none, or only some of them in their SATA drives. For example, the Seagate Barracuda 7200.8 400GB supports NCQ but not 3Gb/s. The Hitachi Deskstar 7K500 is 3Gb/s but doesn't offer NCQ. Today, you need to read the specs carefully and make sure you're picking the right drive features for your clients' applications.

The Best of Both Worlds This SATA drive offers SATA and traditional 4-wire Molex power connections. We prefer this design for maximum flexibility and durability.

Taken together, these new SATA features edge desktop drive technology much closer to the enterprise. In fact, many vendors are now talking about "tiered" storage approaches within larger companies, wherein they might use Fibre Channel or Serial-Attached-SCSI (SAS) for high-level, core storage needs but SATA for applications at the network's edge. Another piece of this puzzle fell into place in February of 2003 with the release of the SATA Port Multiplier specification. This was the last bit needed to facilitate SATA storage arrays of up to 15 drives. For an example, check out Adaptec's Snap Disk 30 JBOD NAS box, a Fibre Channel enclosure stocked with 2TB or 4TB of hot swappable SATA drives.

No one considers SATA to be a complete replacement for SCSI and Fibre Channel. SATA was designed from the outset to be an economical desktop solution along with the several compromises that entails. However, SATA is making significant inroads in the server and workstation markets in internal storage, NAS solutions, and external RAID boxes. With all of the enterprise-class specifications SATA now offers, IT managers are increasingly willing to trust to fault tolerant arrays and replace SATA drives every once in a while. The cost to replace such drives, they figure, will ultimately be lower than paying the premium for traditional enterprise drives up front.

Getting SASsy

In the corporate world, size always matters, and the fact is that parallel SCSI and ATA connectors and cables are too big for the dense server and storage boxes now populating medium-sized business and enterprise racks. Additionally, SCSI more or less hit its signaling brick wall with Ultra320, just as parallel IDE did with ATA/133, and both limitations were being faced at about the same time.

"Technically, we could have stretched SCSI to Ultra 640, but there were some problems with doing that," says Harry Mason, president of the SCSI Trade Association and director of industry marketing with LSI Logic. "So we stepped back and looked at things. SATA was focused on a cost orientation that was inconsistent with some of the objectives of the high volume server market, primarily high reliability, manageability, and high performance. Then we looked at Fibre Channel, and one of the issues there was its still costly implementation. Fibre had made a great deal of penetration into the external storage subsystem market, but that market makes up only about 20% of enterprise-class drives. The OEMs wanted an infrastructure that would accommodate either a SATA drive for the lowest cost per gigabyte or an enterprise-class drive constructed for high MTBF, low vibration, high performance, and that sort of thing."

SATA or SAS? One great advantage of SAS architecture is that it uses the same connectors as SATA, allowing storage device backplanes to accept both drive types in one plug.

The result of the industry think tanks that met on the subject was Serial Attached SCSI (SAS). The beauty of a SAS backplane connector is that it is fully compatible with SATA drives while also working with Serial Attached SCSI drives. The SCSI command set stays unchanged; only the backplane is different. The connectors fit just fine on 2.5" drives, and even 1.8" models are supported.

"There will be a complete transition from SCSI to Serial-Attached - SCSI over the next year," says Joe Cousins, vice president of computer product sales and marketing for Bell Micro, the leading channel distributor of hard drives. "There won't be a choice. Ultimately, all customers will need to transition from SCSI to SAS. The speed of the transition will be dictated by what the manufacturers do and obviously the availability and cost of the associated components with the SAS interface—controllers, cabling, cost to build the drives as the lines ramp, and so on. That's beginning to happen in June, so we'll have our first drives to start sending our customers for evaluation in that time."

Another advantage to the smaller SATA plug size being ported to SAS is that it allows for a second data port. Each port can connect to a different SAS domain for redundancy.

"Dual-port is important because it gives the host multiple paths to get to a single drive," says Jorge Fernandez, Atlas brand marketing program manager for Maxtor. "If something goes wrong with a cable in the path, you have an alternate way to still get to the data. So reliability is increased over what even SCSI can provide. You can also have multiple hosts access the same drive simultaneously with arbitration going on to see who has control of the bus."

In addition to dual-port capabilities, SAS also took a page from Infiniband and incorporated support for up to four channels. A SAS "narrow link" is simply a point-to-point connection between two device ports. However, if two devices have multiple PHYs (physical connection links) within their ports, these can be aggregated. So if you had four PHYs in Port A and four in Port B, you could connect each PHY to its counterpart and aggregate the bandwidth in a 4x "wide port." It takes 16 hard drives to saturate a 4x SAS wide port link.

"You can do incredible bandwidth scaling with SAS," says Fernandez. "Four SAS links configured as a wide port can actually get up to 24 Gbps peak bandwidth, which is an amazing amount of data. Add more wide ports and you can keep scaling that upwards. With Fibre, there was a point where the arbitrary section of the loop became the bottleneck and you would plateau. With SAS, we no longer have that bottleneck, and you can continue to scale and add wide ports up to the 16,000+ device limit."

Unbelievable Access With only one connector, SAS drives function in traditional single-port mode. But make use of the second connector and you can assure continuous disk access in the event of connection failure as well as scale storage bandwidth.

The initial SAS interface will be 3Gbps, but because SAS is full-duplex, as opposed to the half-duplex SATA, actual SAS throughput will be 6Gb/s. SAS also calls for a single connector design reminiscent of WD's SecureConnect. Maximum cable length with SAS is eight meters, and this can be extended with SAS expanders. As with SATA, an external SAS plug specification is in the works for daisy chaining devices.

SAS expanders are central to the format's enterprise appeal, because now, rather than having a 16-device limit within one parallel SCSI domain, SAS can incorporate up to 16,256 devices. There are two kinds of SAS expanders: edge and fanout. Edge expanders can connect up to 128 devices, and a fanout expander (you can only have one per domain) sits at the center of the SAS topology and can connect up to 128 edge expanders. As with a single-device SAS configuration, expanders can connect to either SAS or SATA drives.

"Those expanders get sold into companies that are designing enclosures," says LSI's Mason. "So you'll see storage boxes coming out with a SAS connection to the host on the front end, a SAS connection to the disk drives on the back end, and our expanders will be in those products. We'll also have a line of host bus adapters that get sold to the OEMs and out to the channel."

Companies started demonstrating SAS design prototypes in late 2003. According to IDC, there were 6,000 SAS drives produced at that time. Even though the first batch of SAS products are just now starting to enter production—Fujitsu was the first last March with its two 2.5" SAS models—IDC forecasts that 8.1 million SAS drives will sell in 2007, which is nearly on par with the number of parallel SCSI (8.8 million) and Fibre Channel (8.5 million) drives anticipated for that year.

Drives and Manufacturers

Despite peeking forward to enterprise-class technologies on the horizon, we wanted to focus our attention on disk products best suited to the SMB and consumer spaces. Thus we made the rounds of all the major hard drive manufacturers. Whenever possible, we brought in units for benchmark testing and evaluation. Our test platform was an Intel D955XBK motherboard running a Pentium Extreme Edition 840 (3.2 GHz dual-core) CPU with MSI GeForce 6800GT PCIe card, 1GB of dual-channel Kingston HyperX PC2-5400 memory, and a 250GB Maxtor DiamondMax Plus 9 as our source drive.

We ran five tests at each drive. The highly regarded h2benchw is a command line-based benchmark set from German's c't magazine. HD Tach RW is one of the few conventional Windows-based testing tools with writing capabilities, although both HD Tach RW and Tach RW and h2benchw require that a disk be non-partitioned in order to perform write testing. PCMark 2004's hard drive test set is standard fare. We also compiled two data sets for real world write testing. The first was a 2.0GB compilation of thousands of files ranging from drivers to executables to MP3s to TIFs. The second was a 10.9GB AVI video file. We wanted these two types of data sets to see how different drives would handle sustained writing of a single file versus the start and stop writing of many little files. Note that with the USB-based external 2.5" drives from Western Digital and Seagate, these came factory formatted under FAT32. In order to make the drives handle a 10.9GB file, we had to reformat them under NTFS.

Note that while our test configuration used a SATA/150 drive as the source for file transfers, we did set up an alternate configuration with SATA/300 drives as both the source and target to see if we could realize any benefit from the faster format. Our results showed no benefit whatsoever, which gave us great cause for concern in recommending the technology to end-users as a valid reason to upgrade or pay a premium for the new design. This led us to query a couple of vendors on the subject.

"The data rate coming out of a drive today is not enough to saturate the 1.5 Gbps transfer rate in a drive-to-drive copy for SATA I," says Hitachi spokesperson Beth Ellerman. "The benefits for the faster data transfer rates are most evident in multidrive storage systems where you want to be able to pull pieces of data from multiple drives as quickly as possible."
Maxtor spokesperson Melissa Helms adds that with 3.0 Gb/s SATA "you'll see the most benefit from the interface in multidrive or enterprise environments rather than single-drive desktop environments."

Fujitsu

Since the company focuses solely on 3.5" enterprise and 2.5" small form factor drives, Fujitsu tends to get overlooked in a lot of storage discussions. But in reality, the company has risen to be the #2 2.5" player with 26% market share, according to Fujitsu. The company was first to market with a 100GB 2.5" drive in the last quarter of 2004, first out with a SATA 2.5" drive, and also the first to sample a 2.5" SAS drive back in 2003. Last March, Fujitsu shipped 1.8 million drives, a tripling of output versus the same period two years previously.

Now, Fujitsu is gunning for another first with its 120GB MHV2120AT 2.5" PATA drive, which is now sampling evaluation and qualification units for summertime production. As a 4,200 RPM drive still using the older ATA/100 interface, this unit isn't out to win any performance records. It's all about capacity for road warriors. This is an excellent play for whitebook builders looking to offer higher storage than what most OEMs will be able to offer until they catch up in the fall. Additionally, the 120GB is an excellent upgrade for all your existing whitebook customers chafing under 20GB, 40GB, or 60GB drives. You'll also be able to offer this higher capacity without a commensurate hit to system resources.

SATA Gets Small Fujitsu provided one of the first notebook drives we've seen equipped with SATA rather than PATA. However, in some cases PATA may still yield better performance.

"The new products you'll see in the summertime will have a 20% power reduction given a like RPM and like capacity," says Joel Hagberg, vice president of marketing and business for development at Fujitsu. "We're doing some chipset integration and reducing the power by about 20% across the board on our drives. Also, with the SATA drives, the Intel chipset enables some power saving modes that go along with the SATA spec. They can go into multiple levels of power savings depending on what activities are going on with the system, even to the point of turning off the electrical interface to the drive following long periods of inactivity."

Even bigger news from Fujitsu is the MAV2073 SAS drive, which packs in 73.5GB of capacity with a 10,025 RPM spin rate. This is like having a WD Raptor drive (which also uses two 36.7GB platters to achieve its high specs) but with all the scalability benefits of a SAS interface in a small form factor. Fujitsu still manages to squeeze an 8MB buffer as well as native command queuing into this unit, and the drive sports a 400 G (1 ms) non-operating shock tolerance. Enterprise buyers will appreciate the 1.4 million-hour MTBF rating and the 5-year "no excuses" replacement program.

The SATA interface is just starting to make its way into 2.5" drives, and we were able to sample the goods with Fujitsu's MHT2080BH (SATA) and MHT2080AH (PATA) variants. You'll recall that Western Digital warned us of performance penalties on the desktop with NCQ, and we may have found proof of such here. While the Fujitsu SATA model showed markedly better burst times, all other results trailed the PATA version by a substantial margin. The PATA drive even tied Hitachi for the best time on our 11GB test and realized the best PCMark score of any 5,400 RPM drive.

We should point out that in addition to NCQ, Fujitsu's SATA model includes 32-bit error correction code. We would feel quite comfortable taking a slight performance hit on throughput and trusting the MHT2080BH in arrayed dense server or JBOD solutions.

While Fujitsu doesn't offer an extensive partner program, the company does make its San Jose-based FACT (Firmware and Compatibility Testing) lab for certification and testing available to partners. Unlike many competitors, Fujitsu does not charge for this service.

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