Ubuntu 13.04 Linux Can Outperform Apple OS X 10.8.3
The OpenArena results were mixed between OS X and Ubuntu 13.04. Ubuntu 12.04.2 LTS was slower than OS X 10.8.3 for this older ioquake3 game release but Ubuntu 13.04 generally performed about the same speed as the latest version of Apple's operating system.
With the latest releases of Ubuntu, the Intel Core i5 520M with its integrated graphics were faster on this popular Linux distribution than with the MacBook Pro's own OS X 10.8.3 operating system.