|QNAP TS-870U-RP NAS Network Storage Server|
|Reviews - Featured Reviews: Network|
|Written by Bruce Normann|
|Tuesday, 04 June 2013|
Page 5 of 17
Technology Details: QNAP TS-870U-RP Turbo NAS
The biggest chip on the board is the Intel Celeron G540 CPU, a dual-core member of the 32nm Sandy Bridge family. It's certainly got the biggest heatsink, a densely finned aluminum block held in place by four heavy-duty springs. As much work as the CPU does, it's isolated from directly communicating with most of the subsystems by the Intel Platform Controller Hub, which we all used to call the Southbridge (back when there was also a Northbridge...). This is the second hardest working chip on the main board, and it's also got a heatsink on top, although it's less that 1/10 the size of the one on the CPU. The Celeron CPU in the TS-870U-RP does not have native CPU support for the Advanced Encryption Standard New Instructions (AES-NI) set. These new instructions speed up the encryption/decryption process by anywhere from 3x to 10x, depending on the implementation. As slow as the Atom-based and Marvell-based models are with encryption enabled, the QNAP TS-x70 models are the minimum level that can realistically support AES 256-bit Volume-based data Encryption. Even with the enhanced computing power offered by a Sandy Bridge CPU, the extra load of data encryption is just too much to handle without a major performance hit. If you need volume-based encryption, you really should consider spending the extra to get a CPU that will offer reasonable performance, which means a model that supports the AES-NI instruction set. So far, I have yet to see a NAS product based on an AMD CPU, but the Bulldozer and Piledriver cores are both supporting AES-NI, now.
Marvell supplies the SATA interface ICs for many of QNAP's products, as well as for other suppliers. The ones used on the TS-870U-RP are marked 88SE9125, and they serve as the interface between the system's PCI-Express lanes and the eight SATA devices. Each controller supports two 6 Gb/s SATA interface ports and a one-lane 5.0 GT/s PCIe 2.0 host interface back to the Intel PCH. There are several of these controllers, located on the SATA backplane, which is the same way they were deployed on the TS-879U-RP that Benchmark Reviews tested last year. There is a whole family of parts in this series, and this one is optimized for use with a central RAID controller on the system board. Benchmark Reviews has reported on a number of issues in the past, where a variety of brand new SATA 6Gb/s controllers aren't fulfilling the promises made for this interface. With the latest SSDs pushing more than 4Gb/s on both read and write cycles, many controllers aren't keeping pace. I anticipate the primary usage of the TS-870U-RP as being paired with traditional 3.5" HDDs, none of which operate anywhere near the full capabilities of the SATA 6Gb/s interface. With the right SSDs installed, the theoretical throughput for all of the drives running together would be well over 30 Gb/s, and the rest of the hardware (not to mention the rest of the IT world) just isn't ready for that, yet.
The Xilinx XC3S50A IC on the SATA backplane board is a Field Programmable Gate Array chip, which is basically a programmable logic device that can do anything you want it to. Their main advantage in the marketplace is that they can be developed and deployed quicker and much more cheaply than Application Specific ICs (ASICs). The graphics processor in a video card is a common example of an ASIC, and most of you know how long they take to develop and how much they can cost! In this case, I'm betting that this FPGA is the core RAID controller for the whole system, since I don't see any other devices on the PC board that are designed for that task.
The rest of the major ICs in the system are for power management, and for supporting the various interconnects, like USB, eSATA, HDMI, and GbE. Intersil supplies their ISL6364C and ISL 6314C to provide multi-phase PWM control over the Voltage Regulator Modules that feed the CPU, RAM, PCH, etc. Renesas Electronics (nee NEC) provides their ubiquitous D720200F1 chip for USB 3.0 duties. TI supplies their SN75DP139 DisplayPort to High Definition Multimedia Interface (HDMI) 1.4b convertor chip to drive the HDMI output on the rear panel. The CPU is powered by a 4-phase MOSFET bridge, controlled by the Intersil ISL6364 mentioned above. This image also makes it clear that QNAP is making efficient use of their design resources, by using the same PCB in two similar models, the TS-870U-RP and the TS-1270U-RP.
QNAP relies heavily on Intel for their Ethernet controllers in the high-end models of their product line. It's a smart move, as Intel is a leader in this area, even though they're not very well known for it by the public. Two different ICs combine forces to provide the MAC and PHY functions for the two 1000BASE-T ports on the rear panel; the WGG82574L and the WG82579LM. The latter chip was just launched in 1Q2011, so both Intel and QNAP are keeping things current in this area. We'll see later, in our RAID testing, just how critical Ethernet performance is to a product like this. We'll also see the impact of switching to 10GBASE-T, with QNAP's LAN-10G2T-U, Dual-port 10 Gigabit Network Expansion Card installed in one of the two x8 PCIe slots.
To measure isolated NAS power consumption, Benchmark Reviews uses the Kill-A-Watt EZ (model P4460) power meter made by P3 International. I had both of the redundant power supplies plugged in to the meter, because that's the way 99.99% of users will run a device like this. Obviously, power consumption is going to depend heavily on the number and type of drives that are installed. The power draw also depends heavily on the fan speed that's required to keep the unit cool. When the device first starts up and the fans are going 100%, 275 W is consumed at first, then once the system completes its boot process and gets into idle standby mode, it tapers down to 125W. This is right in line with the 155W specified by QNAP for a system with eight 1TB drives installed. With all eight drives installed and during heavy file transfer operations, it drew 150W during Writes and 140W during Reads. When the system goes into Sleep Mode and spins all the drives down, the power is reduced to 72 watts. When the unit is turned off, it still consumes 5W in Vampire mode; be aware that even when it's turned off, the two SMPS modules still pull a small amount of power.
We've seen the ins and outs of the hardware, the new software, and the technology under the hood; now let's take a detailed look through the extensive list of features that you get with most every QNAP Turbo NAS. I know the next couple of sections are overly long, but it's critical to understand just how much these units can do. You don't want to be fooled into thinking it's just a big box full of drives. It's capable of so much more than that.