Wikipedia
OpenBLAS
In scientific computing, OpenBLAS is an open source implementation of the BLAS (Basic Linear Algebra Subprograms) API with many hand-crafted optimizations for specific processor types. It is developed at the Lab of Parallel Software and Computational Science, ISCAS.
OpenBLAS adds optimized implementations of linear algebra kernels for several processor architectures, including Intel Sandy Bridge and Loongson. It claims to achieve performance comparable to the Intel MKL.
OpenBLAS is a fork of GotoBLAS2, which was created by Kazushige Goto at the Texas Advanced Computing Center.