At first glance, the Raspberry Pi 4 and the Compute Module 4 may appear to be the same minicomputer in different form factors. However, there are subtle and not-so-subtle differences that may not be apparent immediately.
Raspberry Pi 4
The Raspberry Pi 4 Model B is the direct successor to the Raspberry Pi 3. It comes with several significant upgrades over the previous model, such as a faster processor, more memory, dual micro-HDMI output, Gigabit Ethernet, Bluetooth 5.0, and USB 3.0. All these additions make the Raspberry Pi 4 a better PC replacement than all previous versions of the Raspberry Pi.
The Raspberry Pi 4 is not without its competitors as other single-board computers such as the Banana Pi give it a run for its money. Be sure to check out our detailed comparison of the Banana Pi M5 vs. Raspberry Pi 4.
The Raspberry Pi 4 is not without its downsides. It lacks eMMC storage and tends to run a bit hot under heavy loads. Also, availability is a key issue affecting most Raspberry Pi models and the Pi 4 is no different. This has changed recently but it is an issue that tends to come up from time to time.
Raspberry Pi Compute Module 4
The Raspberry Pi Compute Module 4 is the latest system-on-a-module product from Raspberry Pi Ltd. This is the first Compute Module to feature built-in Ethernet. Its Ethernet PHY is also of a more industrial standard, compared to the one on the Raspberry Pi 4, adding support for PTP (Precision Timing Protocol) and PPS (Pulse-Per-Second) timing. It also offers many upgrades over Compute Module 3, such as a more powerful processor, and more memory and connectivity options. The Compute Module 4 is one of the smallest Raspberry Pi models.
The Raspberry Pi Compute Module series is designed for commercial and industrial use. They are essentially versions of normal Raspberry Pis with the ports removed. This allows them to be used in embedded applications. The Compute Module also includes certain features that will be more valued by industrial users; for example, built-in eMMC storage and a PCI Express interface that allows you to connect even more components.
The Raspberry Pi Compute Module 4 must be paired with a carrier board to access the Module’s features. There is an official IO board from Raspberry Pi, but there are several other carrier boards you can put the Compute Module 4 on, such as the Sega Saturn CM4. You can even design your own PCB to pair with the Compute Module, using various online tools.
Raspberry Pi 4 and Compute Module 4: Similarities
Overall, the Raspberry Pi Compute Module 4 and Raspberry Pi 4 are very similar in terms of their core specs and capabilities. Both boards have the same BCM2711 SoC, 1.5GHz quad-core Cortex-A72 64-bit processor, and up to 8GB of LPDDR4 SDRAM. They also share the same VideoCore VI GPU and offer different RAM options.
Raspberry Pi and CM4: Key Differences
1. Raspberry Pi 4 vs. Raspberry Pi Compute Module 4: Price
The Compute Module is more expensive than the Raspberry Pi 4. Comparing the versions of the two Pi models with 1GB RAM, the Raspberry Pi Compute Module 4 is about $5 more expensive. This added cost might not make sense to the average maker, and it tends to compound as you buy more devices.
The price of the development carrier board should also be taken into account. If you are buying the official IO board from Raspberry Pi, it can cost $45 upwards.
Overall, there is more cost associated with the Raspberry Pi Compute Module 4 than with the Raspberry Pi 4. If you are on a budget, the Raspberry Pi 4 is the obvious choice.
2. Raspberry Pi 4 vs. Raspberry Pi Compute Module 4: Target Users
This is the most critical difference between these two devices. The Raspberry Pi 4 was created primarily for hobbyists and tinkerers and the out-of-the-box experience was designed accordingly. You can get a Raspberry Pi 4 running with just a microSD card, a keyboard, a mouse, and a screen. While the Raspberry Pi Compute Module 4 isn’t particularly difficult to use, some users may find it less accessible due to the need for additional components.
3. Raspberry Pi 4 vs. Raspberry Pi Compute Module 4: Memory
All Raspberry Pi CM4 variants come with onboard eMMC storage, except for the CM4 Lite. The eMMC storage removes the need to use an SD card to install an operating system. Also, the read/write speeds offered by eMMC storage are much faster than what you can get with most microSD cards. You can have up to 32GB of onboard eMMC flash storage on a Compute Module 4.
The Raspberry Pi 4 lacks built-in storage and requires a microSD card to install an operating system. Check out how to install an operating system on your Raspberry Pi 4.
4. Raspberry Pi 4 vs. Raspberry Pi Compute Module 4: Backward Compatibility
The Raspberry Pi series, from Model A to Model 4B share a similar footprint and can run virtually the same software applications. That is because backward compatibility is a major priority for Raspberry Pi Ltd. in developing these single-board computers.
However, that doesn’t seem to be the case with the Compute Module series. While Compute Modules 1, 3, and 3+ have the same form factor and can use the same development board, the Compute Module 4 marks a departure. There’s no guarantee that the upcoming versions will use a similar form factor, which can be problematic when releasing products and upgrading them.
5. Raspberry Pi 4 vs. Raspberry Pi Compute Module 4: Specs Compared
Which Is Best for You?
The Raspberry Pi 4 and the Raspberry Pi Compute Module 4 are intended for two entirely different markets, but that doesn’t mean there is no overlap between users. Hobbyists can use the Raspberry Pi Compute Module 4 if they want, while some industrial users may prefer the Raspberry Pi 4. It is crucial to factor in your project’s specifics as well as the availability of whichever Raspberry Pi you decide to work with.
If you are a regular electronics tinkerer looking for the most suitable fit for your projects, the Raspberry Pi 4 was made for you. If you are more interested in creating handhelds, thin clients, cluster servers, or digital signage products, the Compute Module 4 may well be more appropriate for you.
