Ubuntu, Debian, Fedora, CentOS or SuSE Linux.Intel Core 2 Duo processor 1.6 GHz or better.Windows, Mac, Linux, or FreeBSD computer Minimum Requirements - no transcoding The process is CPU-intensive, so an older/slower PC might not be up to the task. playing Full HD media on some smartphones requires transcoding). Transcoding is the process where media is converted from one resolution or format to another (e.g. If however you don't prepare your media ahead of time like this or if you don't have adequate bandwidth between the client and server to play the media AS IS then the Emby Server will assist you by transcoding (converting) your media on the fly in real-time. If you prepare you media in a format that all devices can use, such as MP4 container, using H.264 video with a stereo AAC audio track then you won't need a powerful server normally because all Emby apps can use that format directly.
The hardware requirements for the server will depend on a number of factors including the format of your prepared media, the type of client devices used as well as how much bandwidth is available between the client and the server.