= Introduction =
I have tested the GPU enabled version of AMCL (avialable at http://developer.amd.com/gpu/acmlgpu/Pages/default.aspx).
I have tested it on HD4780 with Ubuntu 8.04 LTS. It requires gfortran version 4.1.2. It only works with this paticular verison. There are two versions of gfortran available on Ubuntu 8.04 LTS. The latest package is "gfortran-4.2"
but this does not work with the AMCL-GPU. Please install the package "gfortran-4.1" explicitly when you try.

= Result =
[[Image(dgemm_4870.png)]]

= Note = 
According to a paper (http://www.vpac.org/files/ACML_Report_lukep_final.pdf), AMCL-GPU automatically switch between CPU and GPU depending on the size of a matrix. I put Figure 1 from this paper here.

[[Image(fig1.png)]]

Basically, for N > 750, AMCL-GPU really use GPU but with a smaller matrix, it only use CPU.