Last week we published Ubuntu 9.04 vs. Mac OS X 10.5.6 benchmarks where we compared the performance of these two popular operating systems on a Mac Mini. With the OS X kernel currently being 32-bit but with support for 64-bit applications, we had used the 32-bit version of Ubuntu 9.04. In a majority of the Leopard operating system from Apple outperformed Canonical's Jaunty Jackalope, but today we are adding in the results from an Ubuntu 64-bit installation. As you can see from the results, the x86_64 version of Ubuntu Linux is more competitive against Mac OS X 10.5.6.