diff --git a/Makefile b/Makefile
index c823f1e8862661ebb103feaf7dae3edbf371c74e..1a2a8c3135aa51b53d9837ce6c4db9e15655ad8b 100644
--- a/Makefile
+++ b/Makefile
@@ -5,10 +5,8 @@ TESTCASE=dem
 PYCMD=python3
 
 # C/C++ compiler settings
-CC=mpicc
-#CC=mpiicpx
-#CC=mpiicpc
-CFLAGS=-Ofast -march=core-avx2 -fopenmp ${MPI_FLAGS} ${LIKWID_FLAGS}
+CC=mpic++
+CFLAGS=-O3 -mavx2 -mfma -fopenmp ${MPI_FLAGS} ${LIKWID_FLAGS}
 #CFLAGS=-Ofast -xHost -qopt-zmm-usage=high ${MPI_FLAGS} ${LIKWID_FLAGS}
 #CFLAGS=-Ofast -xCORE-AVX512 -qopt-zmm-usage=high ${MPI_FLAGS} ${LIKWID_FLAGS}
 DEBUG_FLAGS=
@@ -16,7 +14,7 @@ DEBUG_FLAGS=
 
 # CUDA settings
 NVCC=nvcc
-NVCC_FLAGS=-O3 --use_fast_math
+NVCC_FLAGS=-O3 -mavx2 -mfma
 NVCC_PATH:="$(shell which ${NVCC})"
 CUDA_FLAGS=-DENABLE_CUDA_AWARE_MPI
 CUDART_FLAGS=-lcudart -L /apps/SPACK/0.19.1/opt/linux-almalinux8-zen/gcc-8.5.0/nvhpc-23.7-bzxcokzjvx4stynglo4u2ffpljajzlam/Linux_x86_64/23.7/cuda/12.2/targets/x86_64-linux/lib
diff --git a/examples/dem.py b/examples/dem.py
index 6f426995f0b6f4607ad6eace5d99e9ecfa2f8944..7f3d4d508dad66b372e4000b93a7476116697bae 100644
--- a/examples/dem.py
+++ b/examples/dem.py
@@ -171,7 +171,7 @@ psim.dem_sc_grid(
 #    "data/spheres.input",
 #    "data/spheres_4x4x2.input",
 #    "data/spheres_6x6x2.input",
-#    #"data/spheres_8x8x2.input",
+#    "data/spheres_8x8x2.input",
 #    ['uid', 'type', 'mass', 'radius', 'position', 'linear_velocity', 'flags'],
 #    pairs.sphere())
 
diff --git a/runtime/dem_sc_grid.hpp b/runtime/dem_sc_grid.hpp
index 6f47fc5c50cb881fd72154212f370b13649b6e24..fae3056c12ed5bf8bc4d754246362987b4c441ec 100644
--- a/runtime/dem_sc_grid.hpp
+++ b/runtime/dem_sc_grid.hpp
@@ -113,10 +113,12 @@ int dem_sc_grid(PairsSimulation *ps, double xmax, double ymax, double zmax, doub
             flags(nparticles) = 0;
             shape(nparticles) = 0; // sphere
 
+            /*
             std::cout << uid(nparticles) << "," << types(nparticles) << "," << masses(nparticles) << "," << radius(nparticles) << ","
                       << positions(nparticles, 0) << "," << positions(nparticles, 1) << "," << positions(nparticles, 2) << ","
                       << velocities(nparticles, 0) << "," << velocities(nparticles, 1) << "," << velocities(nparticles, 2) << ","
                       << flags(nparticles) << std::endl;
+            */
 
             nparticles++;
         }