Khadas recently launched VIM3 single board computer powered by Amlogic A311D that delivers the best performance among Arm-based SBC’s I have tested myself, and for instance, Amlogic A311D is significantly faster than Rockchip RK3399, and the platform is quite suitable for Android gaming.
All that power comes at a price however, as Khadas VIM3 starts at $99.99 with 2GB RAM and 16GB storage. That’s fine if you’re going to leverage the features and power of the board, but for some applications, it’s quite expensive. One of those applications is HTPC, as in a world of sub-$50 TV boxes, $100 is a bit too much for watching video content. So the Khadas team is currently developing Khadas VIM3L based on Amlogic S905D3 processor that should provide an excellent platform for HTPC.
Khadas VIM3L specifications known so far:
- SoC – Amlogic S905D3-N0N quad-core Cortex-A55 processor @ 1.9GHz with Arm Mali-G31MP2 GPU up to 800MHz supporting OpenGL ES 3.2, Vulkan 1.0 and OpenCL 2.0, real-time Cortex-M4 core for always-on processing, and 1.2 TOPS NPU (See datasheet for details)
- System Memory – 2GB LPDDR4/4X
- Storage – 16GB eMMC 5.1 flash, 16MB SPI flash, microSD card slot (SDSC/SDHC/SDXC), M.2 NVMe SSD supported (See Expansion for details)
- MCU – STMicro STM8S003 with programmable EEPROM
- Video Output / Display I/F-
- HDMI 2.1 transmitter with 3D, Dynamic HDR, eARC, CEC, and HDCP 2.2 support
- 4-lane MIPI DSI Interface up to 1920×1080
- 10-pin 0.5mm pitch FPC connector for touch panel
- UHD 4K H.265 75fps 10-bit video decoder & low latency 1080p H.265/H.264 60fps encoder
- Support multi-video decoder up to 4Kx2K@60fps+1x1080P@60fps
- Dolby Vision and HDR10, HDR10+, HLG, and PRIME HDR video processing
- Camera – 2-lane MIPI CSI (ISP not built-in)
- Connectivity – Gigabit Ethernet with Wake-on-LAN support; Ampak AP6398S wireless module with 802.11a/b/g/n/ac WiFI 5 2×2 MIMO with RSDB and Bluetooth 5.0
- USB – 2x USB 3.0 host ports (900mA & 500mA Load), USB 2.0Type-C port with OTG & USB PD support
- Sensor – KXTJ3-1057 3-axis digital accelerometer
- M.2 socket with 1-lane PCIe 2.0, USB 2.0, I2S, I2C, ADC, 100M Ethernet PHY interface, and GPIOs
- 40-pin I/O header with pins accessible from
- CPU – USB, I2C, I2S, SPDIF, UART, PWM, ADC
- MCU – SWIM, NRST, PA1
- 2-channel IR receiver
- RTC & battery header
- 4-pin cooling fan header with PWM speed control
- Blue, red and white LEDs
- Power, Func and Reset buttons
- XPWR pads for external power button
- KBI interface to switch between USB 3.0 and PCIe (since both can’t be used at the same time)
- Power Supply – 5V to 20V via USB-C port
- Security – TrustZone based security for DRM video streaming
- Dimensions – 82.0 x 58.0 x 11.5 mm (4x M2 mounting holes)
- Weight – 28.5 grams
- Certifications – CE, RoHS
The company will provide mainline Linux (Linux 5.0+), mainline U-Boot, and the SBC will support Ubuntu 18.04 and Armbian Linux distributions, as well as HTPC-focused firmware such as LibreELEC or CoreELEC, and Android 9.0 operating system. Since Amlogic S905D3 processor is a “D” part we might also have expected support for dual-independent tuners via add-on boards such as VTV Expansion DTV board, but the company did not layout the expansion pads on the bottom of the board like in Khadas VIM2, so it won’t be compatible with the aforementioned expansion board.
Khadas VIM3L will be compatible with the enclosure made for other VIM boards, so you should be able to get a complete kit with the board, enclosure, IR remote control, and power supply. That’s about all we know for now, as availability and pricing have not been disclosed. More information should eventually be posted on the product page and forum announcement.
Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.
35 Replies to “Khadas VIM3L Amlogic S905D3 SBC Targets HTPC Enthusiasts”
Given that HTPC application is the main thrust, would one be unreasonable to expect Netflix approval?
I don’t think it will happen. Last time, I discussed this with another company Netflix was asking for proof of a minimum of X millions of units sold in the US. Maybe things have changed but I doubt it.
The reason is for liability and upstream licensing.
I’m a little bit confused. The article and official Khadas webpage is saying that S905D3 has A53 cores, but in linked SoC datasheet (also official, I believe) lists A55.
Also, I tried to find any documentation about built-in Cortex M4 and/or STM8S003, but I couldn’t find anything. Does Khadas provide at least some code examples?
It’s Cortex-A55. I failed to spot that mistake in VIM3L specs.
The Cortex-M4 is built-in, while the STM8S003 is on-board. (Some of the) Previous VIM boards have this too, so there should be something. Khadas guys will probably answer in comments here.
It’s A55, We’ve just corrected the specs 🙂
A53 is for S905D2 and A55 for S905D3.
Regarding the STM8S MCU, we provide the interfaces for users, you can check the KBI document below for the further details:
@Gouwa Is there any more information on using the Cortex-M4?
I started a thread on the using the M4 cortex. https://forum.khadas.com/t/cortex-m4-amlogic-a311d-vim3/4458/4
Does it have USB3 AND pcie M.2 or is it either or?
It has both, but you can only use one interface at a time because USB 3.0 and PCIe are multiplexed.
Instructions for VIM3(L) users to switch the combo interface between PCIe or USB3.0:
The VIM3L is the same board as VIM3 just replacing A311D with S905D3, right?
Yes, and the S905D3 are full pin to pin with A311D.
What do they mean by non quad core ?
SoC – Amlogic S905D3-N0N quad-core Cortex-A55 processor @ 1.9GHz
There are many different D3 variants, S905D3-K0N/J0N/B0N/D0N/H0N:
K: DTS + Dolby Vision
J: Dolby Version
B: Dolby only
D: DTS only
H: DTS + Dolby
Does that mean the NON does not have any DTS nor Dolby licenses?
Yes, no DTS, no Dolby.
Wouldn’t it be something useful to have if the board is promoted as an HTPC platform? That would differentiate you from the rest of the board too. But maybe the cost is prohibitive?
Yes, the Dolby DTS does a nice feature for HTPC, I will talk with our team if we can get the license from the Dolby company.
BTW, is it possible to build a poll here if users will need this feature? I think the retails price should be at least $5 higher.
I don’t think there’s a way to make a poll in comments. Would that work on Khadas forums? Then maybe share in on relevant communities like Kodi, LibreELEC, and CoreELEC.
I can’t quite remember if licenses are needed for HDMI pass-through though, so it may only be useful for down-mixing. If I remember correctly Kodi does not care about those licenses and supports pass-through and down-mixing in any case. Other programs / apps may not work well.
In that case you should remove the Dolby Vision part from your post. It’s misleading.
“Dolby Vision and HDR10, HDR10+, HLG, and PRIME HDR video processing”
In the board’s current NON version SoC, there is no processing.
The patent for one of the basic dolby licences expired a while back, so as far as I know, could be incorporated without requiring permission.
If you are promoting it as a HTPC platform HDR + Vision is necessary. A middle ground would be to offer it as an add-on option like Pi foundation did for MPEG-2 licenses..
Does anyone know what “low latency 1080p H.265/H.264 60fps encoder” means? For an encoder to work, it has to be able to process a frame in less than a frame time or it can’t handle real time encoding. The other thing effecting latency is how many prediction frames its configured to use. Does this mean that this encoder simply doesn’t support many prediction frames?
Latency in encoding usually refers to how many frames are buffered to allow LongGOP compression to take place. Whilst each frame is encoded in less than duration of a frame, as required for real-time, when you have long GOPs for temporal compression, you buffer multiple frames through the encoder (so you can compare the content between them) and the overall latency can thus be many frames (the encoding is still happening in real time – but there is a fixed latency delay introduced from the time the input frame arrives to the time that frame is output to allow for temporal compression). Lower latency encoders use shorter GOPs (and thus usually offer lower compression ratios or lower picture quality), but lower latency at higher bitrates can be more desirable in some applications than higher latency at lower bitrates?
Thanks, Steve. That’s what I was thinking. Am I mistaken in thinking that the I, B, and P frames are normally a completely configurable set of parameters for video coders? Up to some limits, of course.
You can always pick values lower than the maximum supported and get worse compression/quality, but lower latency. What confuses me here is that to get lower latency, you have to have fewer reference frames (or don’t use B frames) and that means poorer compression/quality and there’s no way around that except for cranking up the bit rate.
That leaves me with my original question, though. To be low latency, you have to cut back the settings of the encoder. Considering that’s configurable below the max values, can’t any encoder be low latency with the right settings? So, saying an encoder is ‘low latency’, it makes me think that they did so by limiting the number of reference frames to a small value. That’s not a feature, that’s a limitation.
Am I missing something? Thanks again for the thoughtful reply.
If it’s aimed at the HTPC user (now modified on the Khadas website to show DIY-HTPC, whatever that is supposed to mean, then the GPIO pins and camera connectivity are not really required, so removing them could make for a smaller board.
It should also be sold in a case with heatsink and supplied with ac adapter as happens with all the other boxes like the GT King.
You would sell way more if it’s a case of open, connect and go.
Having no micro-sd card slot is also a deal-breaker.
How to boot CoreELEC or Linux for HTPC use then?
Must also have a physical power button and AC barrel power connector, supply with at least 5V3A not 2A.
The USB C cable ones are very fragile and stop working if only bent a little. Must also have at least 3 or 4 USB ports to connect hard-drives and remotes controls like Xbox wired or airmouses.
The one USB port doesn’t have enough power to connect even 2 remotes(500mA) and the other USB(900mA) port will have problems with USB hard-drives if the load is 1000-1200mA, so you can only use externally powered hard-drives, this USB port is also disabled if PCIE is used then you only have one USB port with no power for an external hard-drive?
Actually, we design the USB output current at 1.3A and 780mA for USB3.0 and USB2.0 port, but we just label at standard vale at 900mA and 500mA for each.
I find that this can make a really nice general purpose Linux machine. It could easily replace one of my old ALIX running off a 8GB CompactFlash with 256 MB RAM! I’m a bit concerned with the long-term reliability of the USB-C power input though. I would have loved to see a barrel connector next to it taking about 7-20V (let’s say poorly regulated 12V). But I understand it’s not easy given that the board has a really low profile. If at least the power-in connector could be accessible on the board somewhere (even just with pads to solder on), that would be great. As mentioned above, for success it must really be sold with an enclosure. Then I’d have no problems drilling it to install a barrel connector myself 🙂
Responding to myself, I looked at the schematics and board components, and it appears that the black connector beneath the USB-C connector is the DC-IN connector 🙂 Two pins are for the + (marked 12V but 5..24V on the DC-DC input), and two for GND. This definitely is a good design! There’s a case available, so that may indeed become one of my new servers. However the accessories are prohibitively expensive in my opinion. $15 for a fantasist enclosure + $10 for a small heat sink looks quite overpriced. For 1/4 of this FriendlyElec provides a nice, clean, flat, metal enclosure for the NanoPC-T4 (the plastic one only costs $3).
Yes, the model is Molex 78171-0004.
By the way, for small server designs, the heat sink is not needed. I have built haproxy on the board using “make -j 4”, and although it was not fast, the CPU became barely warm to the touch. The board is very small and shipped in a nice rigid little box that some could probably turn into a cheap enclosure by cutting a few holes for connectors into it. I haven’t managed to see the SPI flash yet, and unfortunately u-boot installs on eMMC instead. I’d like to move it to SPI and turn to extlinux.conf or at least u-boot scripts on the eMMC to ease kernel/initrd updates.
Overall the board is very interesting in terms of features and capabilities for this price for anyone willing to build mini-servers. Many boards come with something missing or requiring an extra module (typically emmc, heat sink, or missing USB3 or missing gigabit, or not enough RAM). This one simply has everything by default (considering that heat sink is not needed).
I’ll probably try to make a laser-cut enclosure including a barrel connector for power input and a micro-usb serial console.
> although it was not fast
Can you provide the result of a quick 7-zip benchmark?