
At a glance | |
Product | QNAP Turbo NAS (TS-251A-4G) [Website] |
Summary | Two-bay Intel dual-core Celeron-powered SATA NAS with dual Gigabit LAN, USB 3.0 and HDMI port. Also can be used as USB 3.0 DAS. |
Pros | • Can be used as USB 3.0 DAS • First time configuration via USB • Included remote control • Supports real-time 4K and 1080p video transcoding • Supports Hardware-accelerated AES 256 bit volume encryption |
Cons | • Competing products offer more performance for less money |
Typical Price: $359 Buy From Amazon |

At a glance | |
Product | QNAP Turbo NAS (TS-451A-4G) [Website] |
Summary | Four-bay Intel dual-core Celeron-powered SATA NAS with dual Gigabit LAN, USB 3.0 and HDMI port. Also can be used as USB 3.0 DAS. |
Pros | • Can be used as USB 3.0 DAS • First time configuration via USB • Included remote control • Supports real-time 4K and 1080p video transcoding • Supports Hardware-accelerated AES 256 bit volume encryption |
Cons | • Competing products offer more performance for less money |
Typical Price: $664 Buy From Amazon |
Introduction
QNAP's TS-x51 series is a mainstay of its Home and SOHO product family. We reviewed the original TS-x51 series around two years ago. Since then, QNAP followed up with the TS-x51+, based on a 2 GHz quad-core Intel Celeron J1900 processor, which we didn't review.
This brings us to the TS-x51A family we're looking at today. As in the past, we had QNAP send the four-bay TS-451A-4G, which we loaded with only two drives to generate data for the TS-251A. Both models use the same Intel N3060 Celeron dual core processor, are also available in a 2 GB versions (TS-251A-2G and TS-451A-2G) and can be upgraded to 8 GB of RAM total.
The big innovation the A series brings is what QNAP has dubbed a USB QuickAccess port. The blurb below snatched from the A series product page provides the gist of the feature. Essentially, you get a USB port that looks, behaves and performs like a Gigabit Ethernet port, but using USB 3.0, not Ethernet. This provides the convenience of direct-attach storage, but without DAS performance.
USB QuickAccess in a nutshell
The chart below shows a comparison between the original TS-x51 series and the new TS-x51A models. Though the case sizes and configuration remain the same, the new models have a teal colored strip along the left side of the front panel.
QNAP TS-x51 and TS-X51A feature comparison
The callouts below show the front and rear panel layouts for the TS-x51A models. The front panel now includes an SD card reader as well as the USB QuickAccess port. The rear panel now includes a 3.5mm microphone jack. This will allow audio to be ported to either the 3.5mm output jack or through the HDMI port and enables downloadable programs such as OceanKTV - a karaoke app that runs on your QNAP TS-x51A NAS.
On the TS-x51A models, all three USB ports are USB 3.0. The original TS-x51 models had two USB 2.0 ports and a single USB 3.0 port.
QNAP TS-x51A front and rear panel callouts
Inside
Analysis by Tim Higgins
TS-451A disassembly is similar to the TS-451; you remove the cover, remove the screws securing the drive cage and backplane and lift it off. I wasn't able to find any information on how to upgrade RAM, but this is how you get to the RAM, since it's not accessible otherwise.
Both the TS-251A and TS-451A are powered by a 1.6 GHz Intel Celeron N3060 dual-core processor, sitting under the heatsink in the photo below. Two Kingston DDR3L 2 GB SoDIMMs are used for memory. I couldn't find the flash DoM module QNAP typically uses.
QNAP TS-451A inside
The TS-451A's drive backplane holds a single Asmedia ASM1062 PCIe 2 port SATA controller, which is probably absent on the two-bay TS-251A. The USB QuickAccess port is generated by a Realtek RTL8153 Integrated 10/100/1000M Ethernet Controller for USB Applications. A Realtek RTL8111E Gigabit Ethernet controller sits close by it, so I'm guessing it's also involved in the QuickAccess port's function.
Table 1 summarizes key components for the TS-251A / TS-451A with those for the non-A versions.
TS-251A / TS-451A | TS-251 / TS-451 | |
---|---|---|
CPU | Intel dual-core Celeron N3060 @ 1.6 GHz | Intel Celeron J1800 dual-core processor @ 2.41 GHz (Bay Trail D) |
RAM | 2 GB DDR3 SoDIMM (x2) [expandable to 8 GB total] | 1 GB DDR3 SoDIMM (expandable to 8 GB) |
Flash | None visible | 512 MB DOM |
Ethernet | Realtek RTL8111E (x2) | Intel WGI210TA (x2) |
USB 3.0 | In CPU |
Asmedia 1074 USB 3.0 quad port hub |
SATA | Asmedia ASM1062 (x1 for TS-451 on drive backplane) | Asmedia ASM1061 (x2 for TS-451) |
HDMI | TI DP138 DisplayPort to TMDS level shifter | Asmedia ASM1442 level shifter |
USB QuickAccess | Realtek RTL8153 + Realtek RTL8111E | N/A |