CSCS uses the computer name to connect to it remotely, and to track information about it in our systems. This article describes how to quickly find the computer name.
How to find a computer name (Hostname or UMD number)
Windows
macOS
How to find a serial number / service tag:
For a Dell computer, there is usually a sticker on the case which shows the Service Tag, similar to the below pictures.
Desktop: Laptop: