See the README for the latest system requirements.
As of v.0.4.8, FreeOrion requires an OpenGL 2.1 capable graphic card and a display with a minimum resolution of at least 800x600.
FreeOrion requires at least Windows XP with Service Pack 2 or later, Mac OSX 10.9 or later or any reasonably recent Linux distribution on x86 compatible processors. Other operating systems and architectures have reported to be working by users, but are not actively supported by the FreeOrion project.
Systems with less than 4 GB RAM may have issues saving and loading games with large galaxies that have been played for > 400 turns.