Software

Just like other newer products of the company, the Rival 650 uses SteelSeries Engine 3, which is one of my personal favorites when it comes to drivers. It's a sleek-looking, fast, self-explanatory, and perfectly working program. I couldn't detect any bugs while using it.

The Engine runs in a single window with two main tabs at the top. The Settings tab has all sensor options and the sleep timer, as well as all button-mapping functionality. The Illumination tab has the lighting settings, more about that in the next section. As far as I can tell, you can create an endless number of profiles and macros you can then access over the Configs button in the bottom-left corner. You can also change the view from the top of the mouse to its side, which makes configuring those button easier.

The software roughly takes up 200 MB on the hard drive and consumes about 30 MB of memory while running in the background. If you feel like it, you can delete the software after setting everything up because the mouse has on-board memory it stores these setting to; however, macOS key bindings won't work without it.

Lighting

The Rival 650 has nothing to be ashamed of when it comes to RGB lighting. On the contrary, it has eight individually programmable zones, each of which can be set to a different effect. There are static lighting, breathing, color cycle and reactive key effects, and I've tried my best to demonstrate all of them in the video below. Of course, you can turn off all lighting as well, which improves battery life.