One way the Raspberry Pi 4 differs from previous models is by offering a choice of the amount of RAM (Random-Access Memory).on board. The RPI4 is available in 1GB, 2GB, and 4GB models and are priced as show in bellow.

Although all priced around about the same, no one wants to pay for something they do not need. So which RPI4 is best for you? It is important to understand what RAM is and the role it plays in computing.

RAM is a form of computer memory used to store data temporarily. RAM along with hard drives form the two main forms of data storage used in a computer system. Although both RAM and hard drives are forms of computer memory, both serve different functions in a computer system. In traditional computer system architecture, hard drives serve as the long-term data storage for a system, while RAM serves as a temporary location. Hard drives have much more data storage capacity than RAM.

A good analogy for RAM and hard drives is to think of a desk in a study. When working, the files and papers you are working on are out on your desk. These files and papers are not sorted in any particular way, but are available to quickly access and work on them. The desk/working space is analogous to RAM. There is a limit to how many files and papers you can have out on your desk at any one time. If you there are too many the desk becomes cluttered and disorganized and it becomes difficult to work. To solve this you sort and store away what you are not working on in the desk filing drawers. The desk drawers are analogous to the hard drive. There is more space to store files in the desk drawers, however, sorting and storing these files takes time; so you only will perform these tasks when you are sure you are not going to use the files for a while. To summarize, RAM is used as the CPUs workspace so it can quickly access and perform computations on the data, while hard drives are used for long-term storage.

Now that you know what RAM is and its function in computer system architecture, you can better weigh your options on which RPI4 to buy. So, how much RAM is enough? It depends on your RPI4 application. The reason the RPI4 is being offered with different RAM configurations is that the Raspberry Pi Foundation want the RPI4 to be viewed as a single board computer capable of replacing your desktop. While you can run the 1 GB RPI4 on a monitor like a desktop, it will be slow and clunky because this is computation heavy. Think of the desk with too many papers and files out. This would be especially true if trying to run on two 4K displays, which was a recently added feature to the RPI4.

So why didn’t the Raspberry Pi foundation just make the RPI4 come with 4 GB RAM? At its roots, the Raspberry Pi is a single-board computer, which is cheap and easy to use for many applications. RAM is expensive. In addition to making the RPI4 an option to replace your desktop, the Raspberry Pi Foundation wanted the RPI4 to continue as a cheap available computing option ($35).

So, which RPI4 is right for you? If your applications are going to be IoT or low computing power applications, the 1 GB model is the choice for you. These applications include reading sensors, acting as a controller, or a low-power server. If you plan on using the RPI4 for some of those applications, but may occasionally connect to a single monitor, the 2 GB version is the choice for you. Finally, if you plan on using your RPI4 as desktop, using dual 4K monitors, or running more powerful distros of Linux than Raspbian; definitely buy the 4 GB version.