The current PCIe add-in-card storage market is separated into two general architectures. The first is ground-up, native PCIe designs, such as the Micron P320h. These devices eschew a typical SATA/SAS controller in favor of specialized flash controllers that have native PCIe interfaces. This is where the market is heading. In fact, later this year, you should start to see many more devices that are NVMe-based. But, we will save that discussion for a later time.
The second type of PCIe add-in-card storage takes more of a brute force approach. These devices typically have off-the-shelf SATA/SAS controllers and connect via a PCIe bridge. Think of a HBA/RAID card connected to a SATA SSD, but on a single card. These designs have many advantages and disadvantages. While the cost and time-to-market can be low, they are inherently limited due to the architecture.
Today we are reviewing the Super Talent RAIDDrive II Plus, which employs the later of the two architectures. Prior to receiving this card, my interests were peaked by the raw performance numbers. At 3.2GB/s writes and 2.6GB/s reads, this product should be fast, but it’s weird to see write speeds faster than read speeds when reviewing SSDs. In fact, there is only one other product that I have worked with that has those distinct numbers, the LSI-9265-8i RAID adapter.
Looking at the documentation, there is a good reason why the RAIDDrive II Plus and the 9265 share similar performance characteristics; they share the same RAID-on-Chip (RoC) architecture. The RAIDDrive II Plus uses the LSI 2108 RoC, while the 9265 uses the LSI 2208. Other than PCIe GEN3 support, the RAID cores are identical between the RoCs.
The next interesting piece of the Super Talent puzzle presented itself during POST. The option ROM that loaded was also really familiar. Anyone that has ever used an Areca RAID adapter would recognize it immediately. Other than some light Super Talent re-branding, the configuration ROM is identical to Areca’s.
The final piece is the driver and software. The management software is straight Areca. Although it doesn’t say Areca, the MRAID and ARCHTTP software gives it away. Also, in Device Manager, the RAIDDrive II Plus shows up as an Areca device with an Areca vendor ID and a product ID of 1880. More than likely, the custom firmware was developed jointly with Areca and based on the Areca ARC-1880ixl-8, which, conveniently, uses the same LSI RoC that we discussed earlier.
Before we dig too much further into the details, lets review some high-level specifications for the RAIDDrive II Plus. This device is a PCIe x8 GEN2 add-in-card that fits in a full-height, full length PCIe slot. This product is targeted at enterprise server and workstations, along with the applications they serve, such as date caching, A/V streaming and web server caching.
The RAIDDrive II Plus comes in 480GB, 1TB and 2TB capacities. Super Talent is using 25nm Micron NAND across 8 SSD modules. Each of these modules can be RAIDed by the LSI RoC. Though we primarily tested under RAID 0, the device also supports RAID 5, 6, and 10 along with many more, including JBOD. The system also has 1GB of DRAM connected to the LSI RoC, just as you would see in a standalone RAID adapter. Super Talent does list optional batter backup support, but it is more than likely an external unit and not a part of the board.
Beyond the maximum supported throughput we mentioned earlier, there aren’t a lot of performance numbers listed in the specifications. Much like the RAID adapter it was built off of, the RAIDDrive II Plus lists extensive benchmark numbers based of off many industry used tests. You can find all of these in the datasheet.
The first thing you notice, beyond the large Super Talent cover plate, is the heatsink with the recessed fan. This cooling solution is for the LSI 2108 and is almost identical to the one used on the Areca ARC-1880. While the LSI 9265-8i does not use a fan on its heatsink, we tend to like the fan because it keeps the RoC cool in systems with non-optimal cooling, but it does introduce another point of failure. This probably isn’t a huge point of concern considering the device’s 1.5M hr MTBF.
Directly above the RoC is a row of 128MB Micron DDR2-800 DRAM packages. There is a total of 9 packages, 5 on the front, 4 on the back.
After removing the metal cover, we can now see the 8 SSD modules. The first thing that jumps out is that each SSD module is connected via…USB? That can’t be right, can it? Don’t worry, this isn’t just a large USB drive with a hub. Those modules are connected via SATA, but Super Talent is using USB 3.0 connectors to reduce cost, simplify the design and to make it more modular.
Breaking open one of the SSD modules, you will find two PCBs. The first houses the USB connector and a SandForce SF-2281 controller. The SF-2281 is a single chip solution that does not require additional DRAM. The second PCB is strictly for NAND. Each module has 8 Micron 16GB 25nm MLC NAND. That means our 1TB RAIDDrive II Plus has a total 1024GBs of raw NAND.
Finally, there is an additional power connector along the back of the board. While Super Talent lists this connection as optional, we found that we needed it plugged in for our testing.