compare performance of matrixMul, gtx480 vs tk1 = 230 : 11 GFlop/s = 20 times
compare performance of matrixMulCUBLAS, gtx480 vs tk1 = 660 : 11 GFlop/s = 60 times
compare performance of boxFilter -benchmark, gtx480 vs tk1 = 530 : 77 MPixels/s = 7 times