Z66X Z2 TV box based on the new ZX296716 SoC

Not long ago, someone asked me in the comments about TV boxes based on ZTE Microelectronics’ new ZX296716 SoC.
It caught my interest because it’s not the familiar Amlogic or Rockchip, or even the relatively uncommon Realtek. Since I had the chance, I ordered one for review.


Before getting into the review itself, I think it’s worth noting that this TV box is extremely budget-oriented, despite having 2 GB of RAM and 16 GB of flash storage. So it should be judged as a budget solution, although it surprised me a little in some respects—and disappointed me in others. More on that in the review.


Specifications:
CPU — ZX296716
Number of cores — 4 (ARM Cortex-A53 CPU, clocked at 1.5 GHz)
Graphics — Mali-450MP2
RAM — 2 GB DDR3
Flash storage — 16 GB
Wi-Fi: 2.4 GHz
LAN — 100 Mbps Ethernet
Bluetooth — No
Ports: 2x USB 2.0, HDMI, RJ45, microSD, 3.5 mm S/PDIF jack, 3.5 mm AV jack
Supports 4K resolution
Operating system — Android 7.1
Dimensions — 102 x 102 x 22 mm

There’s also a version with 8 GB of flash storage, but since the price difference is minimal, I don’t see much point in it.

As you can tell from the specs, the new processor is quite similar to Rockchip’s RK3328: the same cores, the same clock speeds, and the same GPU.

The TV box comes in a very common black box, with brief specifications printed on the bottom.


The package includes:
1. Z66X Z2 TV box
2. Power supply
3. HDMI cable
4. IR remote control
5. Manual.


A closer look at the accessories.
1. Manual. I’ve never seen a manual this basic. There’s practically no text, no pictures of the TV box, and even the remote is drawn schematically. In short, it’s not much use.
2. HDMI cable, probably the cheapest kind as well.
3, 4. 5 V, 2 A power supply with a European plug.
5, 6. The remote isn’t programmable. I’ve been seeing these included with the cheapest TV boxes for at least three years now.


The power supply was easy to open, so I did.
I’ve come across this kind of “wireless” mains plug connection several times before, though it’s still not as common as ordinary wires.


The board is probably one of the cheapest designs too. At least they didn’t forget the fuse.


The input capacitors are rated at 4.7 + 2.2 µF. They look exactly alike, apart from the markings, of course.
Here’s something I often mention in power supply reviews: the interwinding noise-suppression capacitor is the “wrong” type—in other words, an ordinary high-voltage capacitor. It’ll work, of course, but in my opinion this is penny-pinching taken too far.
The output capacitor is 1000 µF. There’s a jumper in place of the output filter, and there’s not even a feedback optocoupler; regulation is handled on the primary side.
In plain English, this is a very “economy” power supply.


When I flipped the board over, I expected to find almost complete darkness here. And that’s more or less what I found, though in a somewhat “lighter” version: there’s a PWM controller and overload protection components, so it’s not all bad.

The power supply behaved normally in operation and stayed within a reasonable temperature range. But during a test with the TV box running alongside a hard drive and an HDMI-to-VGA converter, it gave up—the hard drive kept restarting.


The device has a “square, practical, good” design—or, if you prefer, it looks like a chocolate bar.


It measures about 10 x 10 cm, which puts it in the medium-sized category.


The rear panel has these ports:
1. A 3.5 mm jack, which isn’t quite standard for S/PDIF.
2. Ethernet
3. Analog audio and video output (no adapter is included, and without one you only get audio)
4. HDMI
5. 5 V power input

On the left are two USB 2.0 ports and a microSD card slot.

Yes, there aren't many USB ports, especially considering that the device has no Bluetooth.


All the ports in one photo.
Interestingly, you can also read the TV box's name upside down, though then it reads X99Z :)


There are four rubber feet and a few ventilation holes on the bottom.


Before testing, I decided to take a look inside this new model. The bottom cover is held on by three screws; there's nothing under the fourth foot. There are, however, quite a few plugs that are somewhat awkward to remove, though they're sturdy.


There are four RAM chips on the underside of the board, along with a number of small components and a sticker identifying the TV box model.


The antenna isn't glued down; it just sits inside the case. The case itself is a bit odd too. It looks like it was "modified" to fit this board, with several pieces broken off. I wouldn't be surprised if this is an "engineering sample" :)


A metal plate is screwed to the top cover, and heat from the heatsink is transferred to it through a piece of thermally conductive rubber.
The solution is as simple as it is clumsy. Heat is transferred only where the plate contacts the heatsink fins. Why not just use an aluminum block in that case? It would be much more effective.
Still, this solution is so standard among Chinese engineers that nothing surprises me anymore.


The overall board build quality is quite decent, although, for example, the WiFi antenna is soldered to the board rather than connected with a plug. There are also unpopulated areas on the board, most likely for alternative TV box versions.


The heatsink is small, but surprisingly, there was no overheating. I'll cover that in more detail in the testing section.


There's some protection on the power input, but nothing on the HDMI output. In cases like this, I always recommend connecting the output first and disconnecting it last, although I don't follow that rule myself.


1. eMMC memory from Samsung, which is quite good.
2. The RAM is also made by Samsung, using eight chips (four on top and four on the bottom), although these days versions with two or four chips are more common.
3. The WiFi chip is a Realtek RTL8189—not a bad choice, though it lacks 5 GHz WiFi and Bluetooth. The lack of 5 GHz isn't too critical, but going without Bluetooth can be inconvenient.
4. Wired networking is handled by the IP101G. Using a separate chip is also quite useful.


1, 2. The board also has several voltage regulators rather than a single multi-channel one.
3. Power input protection circuit (presumably).
4. Board marking and revision.


Another reason to suspect that this case isn't quite "original": there's an extra rib near the IR receiver, partially blocking the signal from reaching it on the left side.



Software and testing

When you turn it on, a setup wizard starts. You'll need to choose a language, adjust the image size to fit the screen (it was set to 96% initially, so I had to set it to 100%), connect to WiFi, and go through a simple guide to the interface elements.


Since I connected to WiFi during setup, the TV box immediately figured out which city I was in and displayed the weather. It got the time zone wrong, though, but I won't hold that against it.
The interface is a bit garish. I don't know who came up with it, but it definitely catches your eye, though it doesn't really get in the way of using the device.
You can pull up an additional control panel from the bottom; it's hidden by default.


The settings menu is typical of TV boxes sold today: a panel that slides out from the side.
There are plenty of image output settings—I can't remember a single model with more. But there's no CEC control.


There's a nice test pattern for adjusting the image to fit the screen. As I wrote above, it displayed properly in 100% mode.


There are fewer sound settings than video settings, of course, but I think they’re still quite sufficient.


Information about the TV box: Android 7.1 is preinstalled, as stated at the beginning.
You can go on to the main settings menu, but it’s extremely sparse on this model, so I don’t see any point in showing it. I’ll just say that it doesn’t even have display settings.


The attempt to update online failed; there are no updates available.


The TV box has 2 GB of RAM and 16 GB of flash storage. Since it doesn’t come with many preinstalled apps, about 12 GB is available to the user for “personal use.” In my opinion, the 2/16 RAM/flash configuration is the most sensible, but that’s just my opinion.


Additional information and tests.


I’ll put the test results together in a table and add only brief comments here.

In AnTuTu versions 5.2 and 6.1.3, the results are roughly on par with the Amlogic S905 or Rockchip RK3328. Interestingly, version 6.x usually gives a higher score than version 5.x, but this time they were almost identical.


However, AnTuTu 6.2.1 gave a more familiar result, about 10–15% higher than version 5.x.
From the outset, I paid particular attention to the TV box’s temperature, since the tiny heatsink had made me uneasy while I was taking it apart.
But I needn’t have worried: even during testing, I never saw temperatures above 67–68 degrees. The temperature at the very top of the screenshot was recorded at about 65% of the way through AnTuTu.


Performance with both storage and RAM is not very high—I’d even say it’s downright disappointing. The only thing that’s somewhat encouraging is the read speed of the internal flash storage. I’d describe app installation speed as average, but the interface responsiveness is a solid 5 out of 5. I haven’t seen anything like it even on much more expensive models; it feels as if the processor were several times more powerful.
1. USB flash drive
2. microSD card
3. Internal flash storage
4. RAM.


The Geekbench results are, unfortunately, pretty dismal.


PCMark refused to run on this TV box. The app installed, but when launched it showed nothing but a white screen with a bar at the top.
In the end, I ran several versions of 3DMark. Below are the Ice Storm Extreme and Ice Storm Unlimited results.


The Epic Citadel test was surprising—not because it ran at 1280x720, like TV boxes based on many Rockchip chips, or because of its low performance, which was already predictable, but because the results in the different modes were almost identical.
Usually, the results of these two tests differ by a factor of 1.5–2, but here the difference was within the benchmark’s own margin of error.


The Bonsai benchmark, on the other hand, scored a little higher than expected—roughly on par with the Realtek 1295 and slightly below the Rockchip RK3328.


The box’s performance in the AnTuTu Video test was mixed. It stuttered in some of the later tests, for example when playing 1080p MPEG-4 AAC and VP8 Vorbis.


Unfortunately, Wi-Fi is 2.4 GHz only, but that’s to be expected from a budget TV box. Still, it works fine, with above-average sensitivity and speed, “by local standards.”
The screenshot shows three tests: the opposite corner of a large room with a small obstruction, 2 meters from the router, and 1 meter from the router.



Preinstalled apps and multimedia tests.
There aren’t many apps installed—I’d even say it’s just the bare essentials, which is actually a good thing; nothing extra gets in the way.
I’d read that some users had problems with Google Play, so I checked it specifically. It works without any issues.


There’s an app for organizing and playing videos and music, as well as K-addons, which adds plugins to Kodi.
But the more important app is TV store, which you can use to install pretty much anything else you might need.
There are a few caveats, though. For example, Android’s security system thinks this app may be harmful; the warning appeared when I tried to update TV store. I ignored the warning and updated the software.
Next, you can access installation packages for various apps, some of which may already be preinstalled. I think this is a perfectly reasonable approach: install them if you want, and don't if you don't.


Unfortunately, some of the apps either don't work or aren't interesting.
For example, there's an app for accessing various sports news. I'm not interested in that, but even if I were, I'd probably just look it up online.
There's also, for example, Crackle and Animal Planet. They installed, but the first complained that it wouldn't show anything in our country, while the second told me to get lost.


YouTube is also available to install from the TV store.
What can I say? It works, and quite reliably. I tried a lot of different channels, and almost all of them played without any problems. I mostly tested more "demanding" video: 1080p at 60 fps. Unfortunately, though, I found that YouTube only outputs video at 720p and doesn't let you select a higher resolution.


TVMC is basically Kodi. It works and plays video, but somehow the whole thing is... I don't know what word to use... clunky.


For example, I found a channel where you can choose the audio language, as well as the server and resolution. But every attempt I made to watch anything ended in an error.
The same goes for BD rips. The test movie just wouldn't play, "no matter what I tried."


And now a little about alternative software. I started with LOL! TV.
Things are pretty bleak here: some channels return an error, while others play but noticeably stutter. It looks like a lack of processing power or software decoding of demanding video.


And of course, there's the fairly popular Torrent TV. The trouble started right away. First, it refused to show anything until I signed in with my Google account. That hadn't happened before.
As an alternative, it did play video through the Cloud TV software, but with stuttering, and it didn't fill the screen.


All right, I launched it using the included video player. It plays perfectly, with no stuttering, and fills the screen. I couldn't take a screenshot, though, so all I have is a black screen; I included it to show the TV box's temperature during testing.
But "the music didn't last long": after a while (anywhere from 20 seconds to 5 minutes), the video stops and Torrent TV switches to idle or finished mode. Maybe I'm doing something wrong, but as far as I can tell, there's nothing preventing it from playing video.


Testing playback of various video formats.
Here the TV box managed to pleasantly surprise me, especially after the problems with Torrent TV.
I tested quite a large number of different formats, paying particular attention to the "demanding" ones.
1024x768_h265_AC3.mkv
2560x1600_AAC .mp4
3840x2160_AAC .mp4
4096x2160_AAC .mp4
gopro-hero-3-be-avc-high@l5.1-4096x2160-12p-aac-2ch.mp4
GraysPeak8HDR_Dolby AC3.mp4
LG 4K Paris_AAC.mp4
LG 4K Story-of-Earth_AAC.mp4
LG_Chess_HDR.mp4
Philips_UHD_supershopdemo_1.mp4
samsung-note-3-3840x2160-high@l5.1-AAC-2ch-2.mp4
4K HD.Club Changhong-Furano-100mbps.mp4
Sony_4K_HDR_Camp.mp4
Ducks.Take.Off.720p.QHD.CRF24.x264-CtrlHD.mkv (20 Mbps)
Ducks.Take.Off.1080p.QHD.CRF25.x264-CtrlHD.mkv (108 Mbps)
Ducks.Take.Off.2160p.QHD.CRF25.x264-CtrlHD.mkv (243 Mbps)

Not only did the native player handle AC3 audio without any problems, but the video played smoothly too.
The only file with noticeable dropped frames was LG 4K Paris_AAC.mp4.
Even Ducks.Take.Off.2160p.QHD.CRF25.x264-CtrlHD.mkv (243 Mbps) played smoothly. USB 2.0 didn't have enough bandwidth, but since the clip is short, caching apparently helped.

Even the HEVC test files played without any problems, despite users reporting issues with these files on much more powerful systems.
h265-1080-30p-100mbps.mp4
h265-2160-30p-100mbps.mp4



The TV box almost passed the "pixel-for-pixel" output test at 1920x1080. To be more precise, the image was displayed correctly, but there's a small caveat: the horizontal black lines are slightly illuminated rather than completely off. I only noticed this during testing; when watching video, everything looked fine.


As promised above, here are the test results in a summary table.



At the moment, a TV box based on this SoC is essentially the first of its kind, but even now it's clear that for the price, it's a decent choice for playing video files, although it still has some of the software rough edges typical of new products.
I had no trouble playing video files, but ran into problems with online video (I suspect the software hasn't been optimized for the new processor yet). YouTube only worked at 720p, and a Blu-ray rip wouldn't play. But I think they'll iron these issues out over time, either with this model or with later ones.

That said, this processor is clearly not suited to gaming because of its very low performance. The manufacturer has obviously focused on video playback and low power consumption.
Speaking of power consumption, I didn't actually take any measurements, but the fact that it doesn't overheat at all despite its very basic cooling system is reassuring. I really hope the Chinese engineers don't start “optimizing” it by removing the heatsink altogether. During all my testing, I never saw temperatures above 67–68 degrees, and the TV box itself was barely warm.

What I think it's missing? For starters, at least one more USB port, Bluetooth, and support for the 5 GHz Wi-Fi band wouldn't hurt. But now I'm just dreaming.

In short, the processor itself is interesting, and will most likely appeal to the budget segment and to people who'll use it to watch videos. But this implementation is still a bit rough, so it's worth waiting for either a firmware update or some experiments by enthusiasts.

That's probably all. I hope you found the review useful, and as always, feel free to ask questions in the comments.