Best recording device for lazy people?

I would like to capture footage from the "Lutris box" prototype but I don't want recording to affect performance, plus I'm pretty lazy.
I have a good i7 workstation next to the game console that can be used for recording. What would be the best device at this time to record some 1080p/60fps footage of an HDMI output? I'm not looking for something cheap but I don't need any fancy features either, just something that gets the job done easily on Linux.

Also, Jill's chair is a penguin!

Des bisous
- Matieu