I’m an artist interested in making a fairly small-scale project, likely in 2D. I am running OSX 10.9.2, but have hardware somewhat below the recommended specs – Nvidia 330M graphics card, 4GB RAM. Is it at all worth trying to run the engine on this machine, or should I hold off until I eventually replace my computer?
Hi Rengarenk,
Our minimum system requirements are posted in the Frequently Asked Questions section of our main page, UnrealEngine.com.
What are Unreal Engine 4’s system
requirements? You will need a powerful
setup to get started developing with
UE4 right now. 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
These specifications reflect what we feel are the minimum requirements to have a good user experience using the engine.
The engine can run on slower machines in most instances but it is not guaranteed to run or to even provide a good user experience.
The community has put together a forum thread with their machine setups and what their experience is with the engine. The post is titled: [Compatibility List] Unreal 4 - Hardware Feedback]
Take a look there and see if anything matches what you are have or is close. This will give you a better idea than I could about what will best work for you.
I do want to mention as well that the engine is capable of scaling the detail down to give you a better user experience but it will lack features when this is done though. I’m linking the Engine Scalability Settings here to see if this may assist you in what you’re looking for. 
Thank you!
Tim