There are blowfish assembler generation scripts. bf-586.pl version is for the pentium and bf-686.pl is my original version, which is faster on the pentium pro. When using a bf-586.pl, the pentium pro/II is %8 slower than using bf-686.pl. When using a bf-686.pl, the pentium is %16 slower than bf-586.pl So the default is bf-586.pl