While we are unable to test every hardware configuration, we have posted our recommended hardware specifications on our Unreal Engine 4 FAQ:
Here’s what we recommend:
Desktop PC or Mac Windows 7 64-bit or Mac OS X 10.9.2 or later
Quad-core Intel or AMD processor, 2.5 GHz or faster
NVIDIA GeForce 470 GTX or AMD Radeon 6870 HD series card or higher
8 GB RAM
There is also a thread going on the UE4 Forums with users posting their hardware specifications and the resulting framerates along with information about what settings they are running the editor with–here’s that thread:
Hope that gives you a better idea of what to expect with your hardware configurations!
I think Epic should seriously look at highlighting the graphics settings more in the documentation. My laptop was able to run the Cave demo about ~30 FPS on medium, only dropping down horribly in certain parts, but if I had judged the performance solely based on default settings, I might have given up on UE4 altogether. Now I am seeing sample map at 60fps and I don’t have anything to worry about