Raspberry Pi CM5 is 2-3x faster, drop-in upgrade (mostly)

Raspberry Pi Compute Module 5

The Raspberry Pi Compute Module 5 is smaller than a credit card, and I already have it gaming in 4K with an eGPU, running a Kubernetes cluster, and I even upgraded my NEC Commercial display from a CM4 to CM5, just swapping the Compute Modules!

The Compute Module 4 was hard to get for years. It launched right after the COVID supply chain crisis, leading to insane scalper pricing.

It was so useful, though, that Raspberry Pi sold every unit they made, and they're inside everything: from commercial 3D printers, to TVs, to IP KVM cards.

After pre-announcing the CM5 earlier this year, the biggest question was, is it a drop-in replacement?

Yes. For the most part.

I've been testing it in tons of Compute Module boards, and it's been awesome seeing a 2-3x speedup just dropping in the new module.

It boots up in seconds, it has USB 3 instead of USB 2, and it's compatible with PCIe Gen 3 instead of Gen 2. The CPU is 2-3x faster, RAM is 3-4x faster, WiFi's faster, storage is faster... It's basically a Pi 5, but without the plugs. Most CM4 cases and accessories still work with it, just there's a LOT more bandwidth.

The big advantage to a Compute Module versus a Pi 5 is modularity. And I published a video today going over a ton of use cases enabled by various Compute Module carrier boards. All the ones I've tested were built for the CM4, but the CM5 is an instant drop-in upgrade:

I won't cover the individual use cases in this blog post. Rather, I'll focus on CM5 benchmarking and my notes from using the hardware a few weeks.

CM5 Launch Pricing Table

The second-most-asked question is how much it will cost. Put simply, the 8GB CM5 is roughly the same price as the 8GB CM4. The 4GB module is $5 more, and the 2GB module is $10 more. So the cheapest CM5 is now $45 instead of $35—they're dropping the 1GB option from the lineup this generation. For any specific pricing information, please consult the CM5 Product Brief.

Performance

Good news: you can expect almost all the same numbers as a Pi 5 with the same amount of RAM.

Raspberry Pi made some quality of life improvements for management, too:

  • You can edit the EEPROM (e.g. to change the BOOT_ORDER) without needing another computer
  • Raspberry Pi maintains pi-gen-micro to build smaller custom Pi OS installations

CM5 Benchmark - Boot time

Right off the bat, the most refreshing difference is it boots up about 4 seconds faster.

CM5 Benchmark - HPL Linpack FP64

CM5 Benchmark - HPL Efficiency

Once it's running, the CPU is almost 3x faster. And it's also about 1.5x more efficient, according to my High Performance Linpack tests.

CM5 Benchmark - Linux compile

And of course, I had to test recompiling the Linux kernel. The CM5 obliterates the CM4, it's more than 3x faster.

CM5 Benchmark - x264 4K Transcode

CM5 Benchmark - x264 1080p Transcode

Video encoding is also about 3x faster. I tested x264 transcoding both at 4K and 1080p resolutions, using Phoronix. All these benchmarks are helped by the faster LPDDR4x RAM on the CM5, which I tested using tinymembench:

CM5 Benchmark - RAM speed

But all these speedups consume more power, at least at full blast: the CM5 uses almost twice the power flat out. But at idle, the CM5 uses a tiny bit less: I measured 2.3 watts at the wall:

CM5 Benchmark - Power consumption

And if you're deciding on which CM5 to buy, more RAM is better, at least if you're looking for raw performance.

CM5 Benchmark - HPL on various RAM capacities

You can save some money with less RAM, but don't expect the performance numbers on a 2 gig model to match the 8 gig model.

CM5 Benchmark - iGPU GLMark2 V3D performance

The built-in graphics are much faster, too. Just testing with GLMark I saw the score jump from about 750 to 1916. It's not nearly as fast as even an older graphics card, but any improvement is welcome, especially for things like 4K displays.

You might've noticed, there was a third module in most of these graphs, except that last one. That's another CM5, this one being made by Radxa. It uses a Rockchip RK3588S2, which is a monster in its own right, beating the Pi on almost every benchmark, including efficiency.

The elephant in the room is all the Compute Module clones. Because of the Pi shortages, every SBC maker on the planet built their own Compute Module. Though... some work better than others. A lot are faster than the Pi, but pricing is fairly similar, when you compare RAM and relative performance.

The big difference between the Pi and all the others, though, is support. I've written how other SBCs could become Pi-killers—I mean the hardware is often there—but they lack support.

Compute Module 5 and Clones

One big part of that is the breadth of options for the Pi, which may or may not work on other Compute Modules. And if you want to try, you can expect to debug hardware and OS issues yourself. Like I couldn't get a valid GLMark score for the Radxa, because I couldn't get an OS image to boot and use the built-in Mali GPU in time for this post! It's often a frustrating experience.

I regularly test other Compute Modules, though, and I post all my test data and experiences in my sbc-reviews GitHub repo.

Hardware - CM5 IO Board

CM5 IO Board

Along with the CM5, Raspberry Pi's selling an updated IO board, for $20, with a few helpful changes. First, a power button, with the same behavior as the Pi 5. This would've saved so much time debugging graphics cards on the CM4.

Then, there's a new tiny fan header, the same one on the Raspberry Pi 5. Companies like EDAtec already have active coolers for the CM5, and I'll test some cooling options on my my 2nd channel, Level2Jeff.

On the port side, they got rid of the 12 volt barrel jack for power, and now they just use USB-C. They dropped down to two multipurpose Camera/Display ports. Each one has 4 lanes of MIPI bandwidth, just like the Pi 5.

There are still two full-size HDMI ports, an Ethernet port, and two USB type-A ports, but these are upgraded to USB 3. There's a microSD card that only works on Lite Compute Modules without eMMC, and finally an M.2 slot, with a little LED that blinks when you're using an SSD.

This is nice, because probably 99% of people buying these things would plug in storage. On the CM4, you had to use an awkward adapter card, but that's not required anymore.

Maybe we could see this on the Pi 5 someday? Or if not, maybe we could hack it using the Compute Module! That's foreshadowing...

Hardware - CM5

CM5 Silkscreen - RAM and eMMC options

The feature that'll make the biggest impact for me, since I use a lotta compute modules, is this new silkscreen up in the top corner. It has resistors for the RAM and storage sizes, so the specs are right up top.

The major changes from the CM4 include:

  • BCM2712 D0 stepping SoC, with 4x Cortex A76 CPU cores at 2.4 GHz
  • RP1 chip for IO expansion (GPIO, MIPI Camera/Display, 2x USB 3.0 bus, Ethernet)
  • eMMC storage is moved to the bottom of the Compute Module
  • The Wireless chip has been raised up onto a short PCB mezzanine (I believe it can be had separately now, for system integrators, maybe?)
  • The RAM is now an LPDDR4x RAM module, sporting much higher speeds (and on-chip ECC)
  • The Pi 5 PMIC is included on the CM5 board, for USB-C PD negotation or direct 5V input like on the Pi 5

Other things are familiar, like the switchable PCB antenna / u.fl connector, the 2x 200-pin hirose board to board connections, and the Broadcom BCM54210PE (which enables hardware PTP timestamping support).

I've been testing the CM5 on various carrier boards, even with eGPUs and 10 Gbps NICs on the official IO Board, and all that testing can be seen in my YouTube video on the CM5.

Conclusion

CM5 in Compute Blade

But tying up the CM5, Raspberry Pi kept the price the same for the 8 gig model; those start at $75 for the Lite version. For 4 gig, they're going up five bucks, and for 2 gig, it's up 10 bucks, from $35 to $45.

They're dropping the 1 gig model from the lineup, and in reality, a lotta applications choke with less than 2 gigs of RAM, so I'm not surprised.

When the Compute Module 4 came out, it changed literally everything about the Compute Module. Including the form factor. That meant everything built for the CM1 and CM3 had to be redesigned, and it made many hardware developers angry.

Luckily, this time they kept the form factor, meaning for most things, it's a drop-in upgrade, where you get 2-3x faster performance, and at least for the larger models, the same price.

Comments

Is it possible to use it with Turing PI 2?

I haven't tested it on their CM4 adapter board yet. I hope it does work, hopefully I can get to testing that soon! I completely forgot to try, as well as to try on a Home Assistant Yellow (it would make for a nice upgrade for my home and office Home Assistants!

let's hope then sans-wifi version will be easily available, for a change :)

Upgrading the CM5 ram and storage should be easy then ? Just re solder the resistor!

Were you able to test it with the PiBox nas? I would love to take advantage of the performance boost.

You mentioned that small Waveshare IO board just working, did you try to get USB 3.0 working from the CAM0 connector? Or from CM5 in CM4 io board CAM0, DISP0 ones?

I'm intrigued to see how the CM5 compares with a regular Pi5 and whether any of my clunky projects would benefit from me swapping out a regular Pi for a Compute Module.

I would love to know if the CM5 is compatible with the PiBox you reviewed several years ago.

On the charts, red and slightly lighter red for the Pi family are difficult to distinguish. Thanks for the article! Tim

Does it work with desk pi super 6c board which you did a video on showing 6 cm4 boards?

Are you able to test please if not and provide updates as I just got the board and haven’t yet bought the CM modules.

When you compare the 1080p h264 encoding, I guess you refer to the CM4 capabilities without hardware encoding?

Very nice writeup/video, thanks!

Does CM5 support the same number of PCI-E lanes as RPI 5, or was there any change on that regard? It would be interesting to see more PCI-E 3.0 lanes being available in CM5 so other more powerful cards could be used.

Hello Jeff! Thank you so much for such amazing content!

I was wondering what your thoughts are on the CM5, with an appropriate carrier board (though I admit I can’t find any stand alone), and an 8” inch touch screen for a pi tablet? Do you think the CM5 has enough power to make the experience enjoyable?

Thanks!

Hi Jeff,
Have you manage to test this CM5 on the TOFU CM4 carrier board yet?
I'm not sure if it works and provids USB3.0 bandwidth for the TOFU beside the performance boost over the CM4.
Thank you for your great articles

Please give me a use case I haven't already thought of! I need a reason to by a CM...

If you can find an appropriate carrier board maybe a Linux Tablet? The only thing is I'm not sure if the CM5 is power enough for a pleasant user experience.

I was curious as to the relative speed comparing the eMMC memory to a plug-in SSD. Is boot time better with one or the other? or about the same?

Boot times are within 1s of each other (and difficult to measure as precisely as I'd like. The eMMC on CM5 is a good deal faster than CM4, and is faster than most microSD cards I've tested too. Still not as fast as NVMe but adequate for many cases.

About the Raspberry pi logo being up side down... my official Raspberry pi power supply had that too.

Hi Jeff,

You mention that the cm5, for the most part, is a drop in replacement for the CM4. My question is, is the CM4 also a drop in replacement for the CM5, or more specifically can the CM4 be used in the CM5 IO Board??

Regards,
Carsten