up to version 4.5.x openmm is needed for gpu support. For versions from 4.6.x on gpu support is included in gromaces source already.

On VSC-1 Gromacs was built with this cmake command (specifying mpiiccc and mpiicpc did not work here, -DGMX_MPI=ON is enough for compiling with MPI support):

CC=icc CXX=icpc /opt/sw/cmake/2.8.11/bin/cmake -DGMX_GPU=ON -DGMX_MPI=ON -DCMAKE_INSTALL_PREFIX=/opt/sw/gromacs/4.6.5_gpu -DFFTWF_LIBRARY=/opt/sw/fftw/3.3.3_sp/lib/libfftw3f.so -DFFTWF_INCLUDE_DIR=/opt/sw/fftw/3.3.3_sp/include .. 

There might be a problem coming from CUDA, where the intel compiler version is checked. In this case uncomment this part in the /opt/sw/cuda-5.5/include/host_config.h file

//#if defined(__ICC)

//#if !(__INTEL_COMPILER == 9999 && __INTEL_COMPILER_BUILD_DATE == 20110811) || !defined(__GNUC__) || !defined(__LP64__)

//#error -- unsupported ICC configuration! Only ICC 12.1 on Linux x86_64 is supported!

//#endif /* !(__INTEL_COMPILER == 9999 && __INTEL_COMPILER_BUILD_DATE == 20110811) || !__GNUC__ || !__LP64__ */

//#endif /* __ICC */