  We adopt CUDA-capable Graphic Processing Units (GPUs) for Landau, Coulomb and
maximally Abelian gauge fixing in 3+1 dimensional SU(3) and SU(2) lattice gauge
field theories. A combination of simulated annealing and overrelaxation is used
to aim for the global maximum of the gauge functional. We use a fine grained
degree of parallelism to achieve the maximum performance: instead of the common
1 thread per site strategy we use 4 or 8 threads per lattice site. Here, we
report on an improved version of our publicly available code (www.cuLGT.com and
github.com/culgt) which again increases performance and is much easier to
include in existing code. On the GeForce GTX 580 we achieve up to 470 GFlops
(utilizing 80% of the theoretical peak bandwidth) for the Landau overrelaxation
code.
