GMP-ECM 6.3.1 SVN 1588 and GMP-ECM 6.4 SVN 1711 optimized for corei7 64bit.
Built and tested on a Sandy Bridge Laptop: "Core i7 (Sandy Bridge) 2720QM 2.20Ghz" with Windows 7 64bit and Msys + Mingw64.
B1=1,000,000 B2=1,000,000,000
B1=3,000,000 B2=6,000,000,000
B1=11,000,000 B2=40,000,000,000
The testtimes: