Raspberry Pi Compute Module 3 has been released


can you post the link to it, cause somehow i can’t find CM3 on their web page? Or I got it wrong and you just know from private correspondence that they will have it for selling end of January? 10q


Yes, private correspondence; no link to CM3 (yet).


for some reason my PC recognizes the device as a Xbox controller?? tried also manually installing the driver from the zip package on Rasberrys flashing guide but it says the driver is not compatible

EDIT: nevermind. Got it finally to work with rpiboot and now LibreElec 7.95.1 flashed :slight_smile:

Now I just have to see how it work without heatsink. I dont have any here and no idea what should work.


A quick update on the use of Backup to transfer your library and settings over from the CM1 to the CM3.

I used it this morning, and although it works fine with the library, many of the settings don’t seem to transfer, neither do profiles. I certainly ticked all the boxes.

Before the Restore process it did point out that I was restoring to a different version of Kodi, so that may be why it failed partially.

Today I’ve also ordered the bits and pieces to make a suitable heatsink, so that the CM3 will be thermally linked to the Slice case.


What did you order and from where?


If you succeed, can you please post a part list and instructions?


I’ve decided to take the same approach as Gordon, and use thin copper sheet stacked together with thermal paste, the right height to bridge the gap between the CPU and the Slice case.

All the bits should be here early next week. If it works, I’ll post a parts list and some photos.


Is there an easy way to monitor the temperatures on LibreElec / Kodi? Currently i don’t have any kind of heatsink or cooling on the Slice with CM3 and also kept the case closed yesterday. I did watch tv shows (720p and 1080p mkv) and a movie (1080p mkv) and atleast couldn’t see the temperature warning.

But as the Slice case is pretty much closed I am wondering if the heat actually gets out of the case easily.


Theres a termal sensor from the RPi:

cat /sys/class/thermal/thermal_zone0/temp


You should find temperature information in Kodi, as far as I remember, under

Settings - System Information - Hardware

I only get the on-screen thermometer when the CM3 is doing something CPU intensive, like scraping the library. Normal MPEG4 playback places very little strain on the CPU, because there is dedicated H.264 decoding built in to the GPU.

In the future I hope to use the new CM3 Slice to play back H.265 content at 1080p. The decoding for that has to be done in software, so this is where the heatsink becomes important.


That’s correct, I have used that temperature information in Kodi to see how the CM3 is coping - these are the values I have seen:
When it is playing H.264 content, the CPU is barely breaking sweat, clock speed is down to 600Mhz and the temperature is reported as around 60-62C most of the time. For comparison, when it is idle it seems to sit around 52C.
The only time I have seen it higher is after updating the media in the library, when the clock speed was back up to 1.2Ghz and the temperature was up to 71-72C, still well below the temperature where the the CPU starts thermal throttling. But as you say, decoding H.265 content may be an issue without a heatsink.
I’m keen to see how you DIY heatsink works, looking forward to your update - good luck!


In that case I am mainly fine as don’t have any x265 material and mostly watch just H.264 content anyways at the moment.

thanks guys!


Hmm. I have different experience. I restored from a backup made in latest stable Slice build (Kodi v15.2) and everything went smooth, including profiles, plug-ins, settings, library, etc. Only thing which didn’t survive a restore - it’s a “screen” shell command plug-in. But another shell tools like htop and Midnight Commander was restored ok.


Yes that’s true, although I was going to try to boot my Slice using a lite version and then boot from the hard drive. If I can get this working properly then that means you’d just copy LibreELEC builds to the hard drive just like you would to an SD card, meaning flashing the Slice would be much easier than having to install software and following the instructions etc…

Will keep you updated with progress on this!


Hi Gordon.

Does this look like a possibility? I’m holding off ordering a CM3/CM3 Lite, to see if this can be done, should remove any problems of running out of internal flash memory.
If you don’t think it’s a goer, or you’d rather everyone uses a standard CM3 then I’ll order the standard.

Regards Kevin.


Gordon any chance of a YouTube video on this


Is there a way to transfer the MPEG2 and VC1 licences from the CM1 to the new CM3, or do I need to purchase new licences and install those?

Today I tried playing back an old film which is a 1080p .ts file - an MPEG2 transport stream. Even the quad core CM3 struggles here, with stuttering and freezing, and CPU temp straight up to 85 degrees! I assume enabling the MPEG2 licence will cure this.


Having looked into this a little more, I think I can answer my own question :grin:

It seems the MPEG2 licence is tied to the RPi serial number, so it looks like buying a new licence for the princely sum of £2.40 is the way to go.

That’s assuming I can work out the serial number of the CM3 and then work out how to install the licence…__


This site shows where you can find it:



It should be possible to boot from a CM3L, but to do this I first need to get some extra code checked into the firmware (need to program some OTP stuff), this will require you use the rpiboot mechanism first, once this has been done it should be able to boot from the hard drive…

It’ll take some time to get there though because I’ve got a whole bunch of other problems to look at first…



Thanks for that.

I ordered the licence on the RPi website, and it came through last night.

This morning I’ve installed it over SSH and it is working fine.

My 1080i .ts file now plays perfectly, and instead of maxing out and overheating the CPU it now has each core running at <5% :grin:

Happy days.