With the release of the Raspberry Pi 4 having three different models, people are confused about what they should get. I can help you with that choice based on the following information to help you narrow your choice down.
If you plan to attach a monitor to your Raspberry Pi 4 and interface with it directly after it’s all set up and running, buy the 4GB version. There is no stand-alone video memory on the Raspberry Pi 4, so the total system memory is shared for video. Once the system memory is divided up and reserved for the kernel and its modules, any RAMdisk or ZRAM scheme your operating system may be using and the video framebuffer, you’re left with a sizeable chunk of the total marked as unusable for any apps or programs.
You may be able to get away with a 2GB version, which has 100% more memory than the Raspberry Pi 3 B+, but not if you plan on using a 2K or 4K display. If that’s the case, get the 4GB version — it will be worth that extra $20. If you’re going to attach a display you’ll want extra memory to use for the onboard video card.
The opposite is also true, and if you aren’t planning on attaching a keyboard and monitor, you may have no problems using the 1GB version. That’s going to depend on what type of services you plan on running. Something like a cool LED Christmas tree project I did last year won’t need much RAM at all. Something like Gimp, Kodi, or a home-built Wi-Fi access point setup will benefit from more.
In all of my posts, blogs, and vlogs I am using the 1GB version of the Raspberry Pi 4.
NOTE: To get more video performance out of your Raspberry Pi 4 do the following:
Go to your Preferences –> Raspberri Pi Configuration –> Performance
Under the Performance tab, change the value to:
128 for the 1GB model
256 for the 2GB model
512 for the 4GB model