CM3 performance review


Now that the CM3 upgrade has been in operation for a bit, it would be great to see what improvements or disadvantages people are getting from their Slice. Any reviews welcome!


Well I’ve been using the CM3 module for the last week and I must say I’m mighty impressed !!!
The Slice has become everything I wanted in a media player/Kodi box.

All the thing that used to take a few seconds to load are instant now.
Every now and then I came across a video file that wouldnt play video/audio in sync.

Thats all in the past now !
Best upgrade ever for the slice in my opinion. :smiley:

Only downside is that the CM3 module gets a lot hotter and some sort of cooling mod is advised.
But it can be as simple as stacking a few mm of thermal pads onto each other to fill the gap to the top lid.

I’ve used 1x 5mm pad stacked with 2x 4mm pad to cover the CM3 module.
This way it makes contact with the top lid and the case dissipates the heat.
All cores fully loaded and i havent seen anything above 66-67° :smiley:


As said, everything is really quick now: boot, going through big folders…

I have OC mine a little bit (CPU 1300, GPU 500) with proper heat dissipation. But even with this, I still have some videos that are not perfectly watchable. Some h264 with high profile were impossible to watch before, now they are OKish (still some artifacts left, but this is acceptable). Some have no difference between CM1 and CM3 (720 Hi10P usually) and still quite ugly to see / unwatchable. This is using HW acceleration. Tried one video with SW acceleration and got no image.

So worth changing but maybe not the game changer I was expecting.


Hi10 stuff won’t be hardware accelerated @luigibrosse . AIUI there are no current platforms that Kodi runs on that offer Hi10 H264 acceleration in hardware. It’s always done in software - hence the CPU load on high bitrate or high resolution/frame rate content. (I guess the Pi could be using some GPU assistance?)

The Pi will hardware decode 8-bit 4:2:0 H264 as standard (up to at least Level 4.2 - i’ve happily replayed 1080p50 H264 at >30Mbs on both a single and quad core Pi) and VC-1 4:2:0 8-bit and MPEG 2 4:2:0 8-bit stuff with the right licences.

However H265/HEVC and H264 Hi10 will both fall back to software decode (though I think there may be some GPU assistance).


@noggin from what I have seen, H264 Hi10 is still mainly / entirely HW decode (most of it at least), the CPU is not showing that much load actually (if you have your video playing in the background). But it seems like some blocks / instructions are not properly rendered. And this whatever the frequency of the GPU / CPU.

Those are hypotheses. I am not technically competent enough to verify them properly by myself. But I am willing to test if someone has more knowledge to share.