Qnap is a network storage device manufacturer with a wide range of products. The company portfolio contains everything from media players to network storage solutions for security cameras. Its NAS device product line is probably the area where the company has its strongest brand recognition, and the manufacturer aims at offering lots of options.
As a result, many of its NAS devices come in several different varieties. The TS-x59 Pro series is available with two, four, five, six, and eight drive bays, for example. They all share the same base platform: 1 GB DDR2 memory combined with a dual-core Intel Atom D510 CPU.
Using a single platform is justifiable from a business point of view. Offering several varieties of the same basic configuration means serving different customer segments, while keeping development costs low. Taking the TS-x59 Pro series as an example, the two-drive bay TS-259 Pro version (around $599 USD without storage) is targeted toward sophisticated users who require a NAS device for home network use. The eight-drive bay TS-859 Pro is aimed at the enterprise segment, which is reflected in the price ($1580 USD without hard drives). The four- to six-drive bay units cost between $909 and $1249 USD, and might attract both business and enthusiast users.
| Qnap TS-x59 Pro Series | |
|---|---|
| TS-259 Pro | $599 USD* |
| TS-459 Pro | $909 USD* |
| TS-559 Pro | $1079 USD* |
| TS-659 Pro | $1249 USD* |
| TS-859 Pro | $1580 USD* |
* Approximated prices without hard drives; these may vary
Comparing the TS-459 Pro and the TS-559 Pro with four and five bays, the question we want to answer is: are there any differences between the two devices, other than the fifth drive bay? Is it worthwhile for ambitious users to pay extra for the five-bay unit, or are you better off with the four-bay version, in terms of value for money, as well as speed? And finally, what are the advantages of a fifth drive in the NAS device?
As mentioned, all models in the QNAP TS-x59 Pro series share the same dual-core Intel Atom D510 1.66GHz CPU and 1 GB of DDR2 RAM. The Intel NM10 Express chipset only provides two SATA ports, but the TS-449 Pro and TS-559 Pro are equipped with the Intel ICH9R controller as well, thus offering six additional SATA ports with AHCI support. The integrated power supply, two eSATA ports, four USB ports, and two Intel 8257L gigabit Ethernet controllers are available in all models.
Wider Design, Larger Fan
The fifth drive bay makes the TS-559 Pro housing a bit wider than that of the TS-459 Pro (21 cm and 18 cm, respectively). This allows for the use of a large 120 mm fan, compared to the 92 mm fan in the four-drive bay TS-459 Pro. We did not notice any significant differences in noise levels, though. The height (18.2 cm) and depth (23.5 cm) of the two units are identical, though the 5.1 kg TS-559 Pro is quite a bit heavier than the 3.6 kg TS-449 Pro.
(Almost) Identical Front Panels
The front panels of the two NAS units are almost identical. The only differences are the number of drive bays and the power LED to the left of the TS-559 Pro. Other than that, they share the same power button, One Touch Copy button, LCD display, enter/select switch, and status LEDs for eSATA, USB, LAN, and system state. The drive bays are identical as well.
Firmware: One For All
Similar to other NAS device manufacturers, Qnap offers a single firmware for all devices in a given product line. This has the advantage of allowing the firmware to be easily adapted to the different models, since both the hardware and the features are almost identical anyway. The differences are mostly in the details, for example the missing eSATA management menu item on a device without eSATA ports.
Because the TS-459 Pro and TS-559 Pro are based on identical hardware (except for the additional drive bay in the 559 Pro), the biggest differences in the Web-based administration interface are the hard drive identification and RAID mode management menus, with the TS-559 Pro simply allowing for the configuration of one more hard drive. Settings like the choice of file system or RAID mode are the same.
Pretty much all that remains when comparing mostly-identical NAS devices is the assumption that the fifth drive in the TS-559 Pro gives it some kind of performance advantage compared to the TS-459 Pro.
RAID In Theory
The choice of RAID mode and the question of whether the device is mostly going to be used for read or write operation are both relevant. Using a dedicated RAID controller and multiple drives produces a solid performance increase using RAID 5, if you're most concerned about read data rates. RAID 0, 1, and 6 modes also benefit from increasing the number of hard drives for read operations. However, the specific transfer rate increase depends on other factors as well: stripe size, the number of I/O requests, and whether they are sequential or random, not to mention the hard drives you are using. Pretty much the same factors play a role in affecting write performance, although things get a bit more complicated.
The vast majority of NAS devices for the consumer market lack a dedicated RAID controller for managing XOR operations, and that goes for the TS-459 Pro and TS-559 Pro as well. XOR is the basic mathematical operation to create (or restore) data redundancy for an array. These operations are handled by the dual-core Intel Atom D510 CPU instead (also known as host-based RAID), which can have a somewhat limiting effect on RAID array performance.
Take a look at the following pages to find out whether the additional disk in the TS-559 Pro has any effect on transfer rates, and if so, how much.
Test Configuration
We used the NAS devices’ default settings in our benchmarks, meaning no jumbo packets. The firmware (version 3.2.6 build 0423T) proposed the ext4 file system for all the different RAID arrays we tested. Also, instead of using the old 320 GB Samsung HD321KJ hard drives with 16 MB cache we switched to 1000 GB HD103UJ models with 32 MB cache.
| System Hardware | |
|---|---|
| Test Platform | Asus P5E3 Deluxe, Rev.1.03G, LGA 775, Intel X38, BIOS: 0810 (02/11/2007) |
| CPU | Intel Core 2 Duo E6750 (65 nm Conroe core) @ 2.66 GHz |
| RAM | 2 x 1024 MB Crucial Ballistix DDR3-1600 |
| eSATA Controller | JMicron JMB363 |
| System Hard Drive | Seagate Barracuda 7200.9, 160 GB, 7200 RPM, SATA 3Gb/s, 8 MB Cache |
| Test Hard Drives | 5 x 3.5" Samsung Spinpoint HD103SJ, 1000 GB, 7200 RPM, SATA 3Gb/s, 32 MB Cache |
| DVD ROM | Samsung SH-D163A , SATA 1.5 Gb/s |
| Graphics Card | Gigabyte Radeon HD 3850 GV-RX385512H GPU: 670 MHz, Memory: 512 MB DDR3 (830 MHz, 256-Bit) |
| Network Card | Marvell Yukon 88E8056 PCIe Gigabit Ethernet Controller |
| Sound Card | Integraded |
| PSU | Cooler Master RS-850-EMBA, ATX 12 V V2.2, 850 Watt |
| System-Software & Treiber | |
| Operating System | Windows Vista Enterprise SP1 |
| DirectX 10 | DirectX 10 (Vista-Standard) |
| DirectX 9 | Version: April 2007 |
| Graphics Drivers | AMD Radeon Version 7.12 |
| Network Drivers | 9.0.32.3 (Vista-Standard) |
| Intel Chipset Drivers | Version 6.9.1.1001 (20/02/2008) |
| JMicron Chipset Drivers | Version 1.17.15.0 (24/03/2007) |
Intel NAS Performance Toolkit
We used the Intel NAS Performance Toolkit for testing the NAS devices. For a more detailed description of the benchmarks, see the article Benchmarking with Intel’s NAS Toolkit.
Noise Levels (Subjective)
Both the TS-459 Pro and the TS-559 Pro are rather quiet NAS devices. The only time they are actually noisy is when powering up, as the fans are briefly operated at full-speed. In normal use, you only hear a slight hum that is hardly audible and hence not annoying.
We did not notice any major differences between the TS-459 Pro with its 92 mm fan and the TS-559 Pro with its 120 mm fan. The quiet impressions made by the two NAS devices were somewhat disturbed by a recurring noise caused by the vibrations of the hard drives. Applying a slight pressure on the hard drive cages immediately silences the humming noise, until it turns up again at some point. We would suggest better vibration cancelation for the hard drive mounting points.
Power Consumption
| Qnap TS-459 Pro | Qnap TS-559 Pro | |
|---|---|---|
| Off | 0.7 W | 0.9 W |
| Peak | 110.5 W | 148.8 W |
| HDD Power Down | 24.4 W | 27.3 W |
| Idle | 45.1 W | 56.2 W |
| Rebuild | 52.2 W | 63.5 W |
The power consumption at idle (power down) does not differ a lot, and active idle differs by roughly 10 W. In any case, both NAS devices require roughly as much power as a low-power desktop PC, which is acceptable. Roughly half of the power consumption is attributed to the hard drives, while 15-25 W are required by the Atom D510 platform.
We have summarized the results and organized them by RAID mode for better overview. The four-drive bay Qnap TS-459 Pro is represented by the blue bars in the charts below, while the five-drive bay TS-559 Pro is represented by the green bars.

The HD video recording test consists of 100% sequential data writes, and only really shows a difference in data transfer rates in the RAID 5 mode. In RAID 0 they are quite similar due to the gigabit network port posing a bottleneck. We attribute the marginal differences in test results to measurement margins of error. A similar picture emerges in the RAID 1 mode, with the 2.6 MB/s difference being rather low. The gaps between RAID 5 and 6, at 7.1 MB/s and 8 MB/s, are a bit larger.

The sequential read operations in the HD video playback tests are quite similar. In RAID modes 0, 1, and 5, both NAS devices are at pretty much the same level of performance. The fifth hard drive in the TS-559 Pro becomes valuable in the RAID 5 degraded mode and RAID 6 modes, where the performance benefit speaks in favor of the five-bay version.

There are hardly any noticeable differences in performance between the NAS devices when working with huge amounts of very small files (photo album, four bytes to 102 KB) either. The difference in the RAID 6 mode is lower than when reading or writing sequential data. Only in the degraded version of the RAID 5 mode is the TS-559 Pro able to achieve any higher transfer rates.
More benchmark results can be found in the gallery.

The simulated system backup into a single container file (66% sequential writes) is not significantly faster on the TS-559 Pro. Once again, the differences are larger in the RAID 5 degraded mode and RAID 6 mode.

Restoring the backup produces very similar results.

The difference between the Office Productivity benchmark compared to the Photo Album benchmark is that the files not only have to be read, but written as well. Also, the file sizes vary between 12 bytes and 197 MB. This means that the differences in data transfer rates are very small in the RAID 6 mode. The difference is measurable in the other RAID modes, but so small that it is practically irrelevant.
More benchmark results can be found in the gallery.
With the TS-459 Pro and TS-559 Pro, Qnap offers two NAS devices in the upper class of the enthusiast segment that are a attractive when it comes to build quality and equipment, as well as features. We are not surprised to find that the suggested target audience includes small and medium businesses, too. The range of products is nice and broad, as Qnap’s portfolio stretches from two-drive NAS models to heavyweight eight-drive models for business applications.
For enthusiasts and ambitious home users, the four- and five-drive bay NAS models are probably the most interesting ones. At around $900 and $1100, they are far from affordable for home users, but attractive for small businesses and enthusiasts on a larger budget. However, our question is whether you should spring for the model with four or five drive bays?
If you were speculating that the extra hard drive in the TS-559 Pro would bring some extra speed to its RAID array compared to the four-bay version, prepare to be disappointed. Our benchmarks only show performance differences in the RAID 5 degraded mode and RAID 6 mode.
But there are arguments for the TS-559 Pro other than faster transfer rates. It obviously has a higher maximum storage capacity and allows for more flexibility when it comes to the configuration of RAID modes. Depending on the requirements, the TS-559 Pro could be set to run two hard drives in RAID 1 mode, while operating the remaining three hard drives in a RAID 5 array. Security-conscious users should be particularly attracted by the possibility of running four drives as a RAID 5 array, ensuring a high storage capacity, and use the additional available hard drive as a hot spare drive or drive for temporary data. Speed is not the highest priority in that case, anyway.





