Spine is a desktop productivity app, but it is written like a game: it uses OpenGL and draws at 60+ frames per second. Spine is somewhat boutique in that it uses its own UI very efficient UI library. Fast graphics hardware is helpful but usually unnecessary, as 2D just doesn't use anywhere near the resources that 3D does. Spine benefits from a fast CPU, but typically you won't notice the difference unless your project has many tens of thousands of attachments, skins, and other items.
In short, Spine is very efficient and can run on nearly any computer. The official requirements are OpenGL 2.0 or higher with the FBO extension (released in 2004).
