I haven't tested on a large variety of machines but I developed and shown it off using a ~10 year old laptop and would get 60fps. Specs are:
- CPU: Intel Core i5 m460 dual core (2.53 GHz)
- 4 GB Ram
- GPU: AMD Mobility Radeon HD 5000 Series
The launcher also let's you turn down the quality pretty easily to run on machines even lower end than that. My other laptop is about the same but with an integrated graphics card and I would need to turn quality down pretty low but it would get me 30+ fps.