New M.2 extender board pinouts reversed

Received my new shorter M.2 extender board yesterday with no instructions. It comes with 2 ribbon cables, which are longer for folks who intend to mount the board on top of the SBC (improving access to the microSD slot). I noticed that the contacts on the ends of the cable are now on opposite sides.
But, when I examined the board’s M.2 connector, I could see that the contacts grip the ribbon cable on both sides. In other words, it didn’t appear to matter which side of the ribbon cable has exposed contacts, from an electronics perspective…so I thought.

When Radxa moved the M.2 connector to the opposite side of the extender board from the SSD, they also reversed the pinout order!

Now, I have a dead Rock Pi 4B.
Perhaps @jack or @luffy… someone should inform Radxa that they need to provide their customers with some installation instructions, which includes a fair warning that the pinouts on the new M.2 extender board have been reversed. That would have avoided this from happening.


I just received mine too, no instruction whatsoever, checked allnet, no instruction either. @jack you really need to post the instructions somewhere accessible, the installation is not an intuitive process.

Besides, since you are providing 2 ribbon cables, why not include a shorter one so it won’t stick one inch out of the edge when using regular standoffs?



I am really sorry for this. Indeed we did not thought people would mix the cables. We will put the instructions on the wiki:

The pinout is reversed because the connector is now at the bottom, the routing is straightforward if we reverse the pintout. So the FPC cable is changed to pin on dual sides.

I am sorry for your loss. We will send you another ROCK Pi 4. For the Samsung SSD, I am not sure the warranty in your country. Here in China, we can replace for a new one within 3 years.

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As others have mentioned, if the M.2 extender board is mounted above the Rock Pi’s mainboard, the FPC cable blocks access to the microSD slot. Radxa kindly provided the longer FPC cables at their requests, but as I’m sure some have discovered, the longer FPC cables still restrict access to the microSD slot.

This issue can be solved by mounting the M.2 extender board under the heatsink, using a shorter FPC cable. The shorter FPC cable is ideal, because it allows the Rock Pi 4B to be installed inside a case, while allowing the microSD slot to be within reach.

The assembly procedure for connecting the ends of the FPC cable is exactly the same as described on the wiki page. The only difference is in where the M.2 extender board is mounted, after the connections have been made. If a shorter FPC cable were provided (perhaps one of each, as before), it should also have contacts on opposite sides to avoid any confusion. Then, the same instructions about ensuring that the contacts face the board applies to both options.

Of course, if the Rock Pi 4B, a large heatsink, and SSD are enclosed inside a case, cooling fans should be implemented to provide adequate airflow between the heatsink and SSD.

If the M.2 extender board included illustrated instructions in the packaging, it would be more effective method of avoiding accidents, for the benefit of customers who are not aware of the wiki.

Hi, @jack .
Provided link really broken, no content there:

Good job regarding the instructions on the wiki link.:+1:
I would suggest adding a warning about over tightening the M.2 shim to the mainboard. As others have found, it could bend the M.2 adapter board onto the eMMC module. @luffy is also aware of this issue. As I have suggested, nylon washers placed in between the mainboard and adapter would ensure this didn’t happen.

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Instructions are on the wiki link, now.:sunglasses:

Indeed, I wondered there is no instructions supplied, I lately received additional package of m2 extenders and there is no instructions how to install too. However, everything seemed logic to me and cables were marked with blue on upper side which kinda made sense but still, you cant know it and I agree, instructions should have been added, something like qr would even save on paper. What I wasnt sure about is why 2 cables were delivered and if they are different, so I tried my luck, luckily nothing is damaged.

I did place it under rockpi board, if somebody says he requires better access and places it over cpu heatsink to gain better access to SD slot, then I would hope RADXA to add some kind of a heat shield beetwen the heatsink and m2 board. However, I preffer to split them as far possible from each other as they both produce heat, I actually placed the upper part of acryl housing between rockpi and m2 board, however, I had to use additional bolts etc because there is not enough for such construction delivered. As for SD access, I do not think that I need it more often than few times when I reflash or recover because internal emmc or disk are broken. So far you can place SD card, if you have tweezers, you can use them to place SD card easily into the slot.

If somebody bought acryl housing, then one (upper) side is unused due to the huge heatsink, I hope RADXA will consider adding few bolts more either to m2 package or rockpi4 housing itself.

EDIT: And yeah, if you look up picture 4 on wiki guide, then it isnt actually how I would like it to be, I would like if heater is on lowest level heats everything up and if you flip it, you place full weight on your M2 which probably is also not good, thats where I place and used acryl housing, lower part of it is first, then there is enough room for M2 board on which are heatsinks for M2, then the upper part of acryl housing, then rockpi board itself, then big heatsink, will maybe make a pic when I am back home.

One additional thing, bolts etc transfer the heat, maybe using different materials would end in less temperature on device.

EDIT3: here a pic of one device without m2 disk

If there is SD extender cable (which there is) and it is long enough (which I think it is) then it can be moved between m2 board and acryl to the opposite for best access as your device is mostly turned to you with USB side, which would bring SD to the same side

EDIT4: this is another device, where the cable does go differently and with this construction, access to SD is slightly worse than the one of previous device, just due to different cable placing, you can see inserted SD card and M2 disk

Here you see that there is enough place for heatsink for M2, even for those delivered with acryl casing (as I had huge heatsinks, small were delivered with acryl case, so I though, why not using them to cool down M2 from my old notebook which was in notebook without any cooler on it:

EDIT5: M2 extender board cant be properly placed if there is eMMC card, it must be done gently, otherwise it could break by the pressure caused due eMMC card being higher, which I bet many users would be confused if they do it right, especially as there is no guide and no pic with installation when eMMC card is also installed. With that we would be back at point of criticism that main installation guides included only steps how to flash with some third party instead of how to flash directly from SD card to internal emmc (with dd as example which works on rock itself, not like suggested soft which doesnt), because if I have to take out emmc, I have to reassemble whole device, which is nasty. Last point of criticism connected to it would be RADXA not providing offline image for internal flashing, as for that it is enough to simply add compressed image into the image itself which would simply result in double size of current image but would provide everybody ability to flash devices right after they prepared their SD card. For me and my releases, I included all flash scripts as well as things like autoflash of m2 disk on first boot if FLASHM2DISKDEFAULT exists on first boot, that way installation and setup of rockpi is for me very simple, regardless of where I want to install it, I described it without to many details here: Installing images with DD, no need for emmc adapter, run on USB3 or M2 per default

I thought the m.2 extender went opposite side from the CPU as hopefully the heatsink, M.2 extender & RockPi4 turn up tomoz.
I must admit from reading I am confused and a little worried about assembly.

What version is this?

the cpu is right above:
maybe this is better pic:

Not really lols, apols, as in pics.

I was just going to have the heatsink at the bottom and the m.2 on the top.
Its wondering “reversed connector” hopefully you mean native without extender m.2 cards should be inserted upside down as basically the ribbon and extender board flip it the other way.

Just noticed the edits yeah those are clearer.

You can place it above, I tried this configuration @stuartiannaylor and I would not advice to do so if you dont heave airflow or heatshield beetwen them, I also tried putting acryl over as heatshield which results in heatsink heating much more and much faster than when there is nothing above. If you look up most desktop mainboards, you will find cpu on upper part, gpu somewhere in the middle and m2 mostly on gpu height or lower. All of them produce the heat but if you place cpu on lowest place, then heat will go up and heat up other devices. For M2 is heat performance killer, I wouldnt advice to have m2 extended board over the heatsink

BTW, @RADXA this broke:

it happened 4 days after I used it, your bolts have not that good quality, I would maybe ask the manufacturer, not sure if it is due to the heat or not, but I wouldnt expect a bolt to break

So I am presuming things get a little toasty, haven’t got delivery yet and have been wondering how much conduction an upside down heatsink will give vs convection.

I have a m.2 sata board just to try out, but thinking things must be very toasty if its thermal throttling.
Postie arrives tomoz, so we shall see.

@stuartiannaylor I think you will be happy and satisfied ;), it is always better to check in front like you do, education is a cure :slight_smile:

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I am actually quite excited as been following and playing with SBC since the Pi1 and with Kernel 5.2 & the Mesa Gallium drivers with the right DTS things start to become much easier and more normalised in terms of drivers and hardware.
Prob like normal with me, my expectations will be off the mark, but I do really like the form factor of the RockPi4 and that RK3399 does just scrape into what I call entry level computing, so I should have quite a few projects to play with :slight_smile:

Compared to any raspberry pi, they are not comparable :). For raspberry pi you can find more stuff finished, here you will have to dig by yourself some stuff which is ok as rockpi4 is quite new. As for games on ubuntu/debian, I did not install steam or any games for now, but most old games should work with emulating, maybe except worms world party

btw, rasberry announced to release raspberry pi4 which is actually the same as current rock4 by description, however, they just plan it and no devices will be available until 2020, with that, raspberry is dead for me but will find its use for simple things where I wouldnt say its chepear than rock devices with 1GB, but yeah, who needs prepared soft or is a newbie will maybe install everything faster, but then the usage of it will suffer due to performance compared with rock4

I use it mainly for crypto stuff and penetration test if I need some, its cpu’s are also fast enough to compress xz on the fly, gpu is strong enough to show HD if I ever turn it to a tv box (which I will not). Not all forensic packages can be installed by default for now, there are some missing dependencies which you can easily compile by yourself.

I am not all that sure about the Pi4 as far as I was aware Pi is purely an incremental upgrade with what will be VideoCore5 and they are keeping strongly backward compatible due to the commercial side of raspberry and what is needed for education is sadly being overlooked.

Heard it was going to be 2020, but just this gut feeling they are going the same direction most successful UK technology companies go and prob eventually bust before they figure out maybe something new that fits the market.
They are far too intertwined with Broadcom and proprietary hardware of pseudo opensource.

I am the same with Tv / retro games but I will be installing and seeing what works and maybe providing a few images to make things slightly easier for some.
Manjaro might be also including support for the RockPi4 which is something I aim to try myself.

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the more distros we have, the better it is, but having stable distros should be priority and for now RADXA did not manage to get stable software out with device release, but we shouldnt be to critical, as providing operating system to public is always something with risks of something not working the way it was meant to be, or simply some kernel stuff upgrade which shows that your implementation was wrong, etc, etc… I am satisfied that all images I tried out worked out of the box, debian one is buggy, if you upgrade, you break some stuff resulting as example in browsers not working anymore which is a killer for a newbie who would be dependant of browser to look up and copy commands.

Taking wrong path could be done much earlier than you think, just look at huawei and what is going on, who can guarantee me that rockpi’s will not be banned too? Today, longterm plans of 10-20 years are nothing worth as the world, technology and everything around changes much faster making many of such plans obsolete after 1,2 years