There didn't seem to be one, so I compiled and uploaded a Pentium 4
version of GMP-ECM into the usual place in the files area. As the
others, it requires cygwin1.dll. Here are the timings of all
versions for a 136 digit composite using B1=250000 on a 2 GHz Pentium
ECM version Step 1 Step 2
athlon 19.1s 8.0s
i386 19.6s 8.3s
pentium 15.1s 7.1s
pentium2 17.3s 7.7s
pentium4 6.6s 3.7s
For comparison, my Athlon 1800+ takes 6.1s, 3.1s in the same test.
The P4 optimized version is much faster than the others and nears the
speed of an Athlon. Have fun factoring!