PS3's hardware has also been used to build supercomputers for high-performance computing. Fixstars Solutions sells a version of Yellow Dog Linux for PlayStation 3 (originally sold by Terra Soft Solutions). RapidMind produced a stream programming package for PS3, but were acquired by Intel in 2009. Also, on January 3, 2007, Dr. Frank Mueller, Associate Professor of Computer science at NCSU, clustered 8 PS3s. Mueller commented that the 256 MB of system RAM is a limitation for this particular application and is considering attempting to retrofit more RAM. Software includes: Fedora Core 5 Linux ppc64, MPICH2, OpenMP v 2.5, GNU Compiler Collection and CellSDK 1.1. As a more cost-effective alternative to conventional supercomputers, <answer>the U.S. military</answer> has purchased clusters of PS3 units for research purposes. Retail PS3 Slim units cannot be used for supercomputing, because PS3 Slim lacks the ability to boot into a third-party OS.
Who is buying PS3 clusters instead of supercomputers in order to save some money?
the U.S. military