 We find that high single-core performance and a correct choice of the number of cores used on the chip are the essential factors for lowest energy to solution with minimal loss of performance .
<clarity>  We find that high single-core performance and a correct choice of the number of cores used on the chip are the essential factors for lowest energy to solution with minimal loss of performance .
 We find that high single-core performance and a correct choice of the number of active cores per chip are the essential factors for lowest energy to solution with minimal loss of performance .