This question was answered by @jtittle:

@Polv89

You can do a “soft” upgrade which will perform CPU & RAM updates by:

• 1). Log-in to the DO Control Panel @ https://cloud.digitalocean.com
• 2). Click on the Droplet you want to upgrade (i.e click the hostname).
• 3). Click on “Resize” - You’ll see that you need to shut the Droplet off first so;
• 4). Click on “Power” and then click on the second tab labeled “Power Off.”
• 5). Once the DO Control Panel gives you the OK, click on “Resize” once again to pick an upgrade.

Important things to keep in mind:

• 1). You won’t be able to downgrade once you upgrade. You’ll have to take a snapshot (backup), create a new Droplet and use the Snapshot as your template instead of one of the OS templates.
• 2). Doing a “soft” upgrade (or fast-resize) won’t upgrade your disk space. You’ll need to do #1 to upgrade disk.

View the original comment