AMD64 timings using ISO C mult 512-bit: 496 1024-bit: 1717 2048-bit: 7200 sqr 512-bit: 448 1024-bit: 1760 2048-bit: 7099 mont 512-bit: 1416 1024-bit: 5156 2048-bit: 20820 expt 512-bit: 1520207 1024-bit: 10603520 2048-bit: 84893649 using amd64 mult 512-bit: 292 1024-bit: 945 2048-bit: 3620 sqr 512-bit: 238 1024-bit: 801 2048-bit: 2853 mont 512-bit: 731 1024-bit: 1730 2048-bit: 5462 Exptmod: 512-bit: 641743 1024-bit: 3167406 2048-bit: 20158609 LTM exptmods Exponentiating 513-bit => 825/sec, 2183028 cycles Exponentiating 1025-bit => 151/sec, 11900720 cycles Exponentiating 2049-bit => 24/sec, 72376416 cycles