Hardware and internet requirements for 1080/30p streaming, if video source is external
Connection Speed

For H.264 1080p30 streaming with typical compression (6 Mbps), I would recommend an Internet upload speed of around 10 Mbps minimum.

Hardware

OBS Studio suggests the following system requirements:


AMD FX series or Intel i5 2000-series processor (dual or 4-core
preferable) or higher.
At least 4 GB of RAM (recommended, but not necessary).


For Windows:


DirectX 10.1 compatible GPU.
Windows 7 SP1 or newer.


For macOS:


Intel CPU (PPC is not supported).
OpenGL 3.2 compatible GPU.
macOS 10.11 or newer.


As for mobile streaming, 4G LTE (between 2-5 Mbps) can manage 1080p30 - albeit with high compression.