for P3 1G, compare speed and stability...
CFLAGS="-O2 -march=pentium3 -pipe -fomit-frame-pointer"
CXXFLAGS="${CFLAGS}"
and
CFLAGS="-O3 -march=pentium3 -pipe -fomit-frame-pointer -fforce-addr -ftracer -momit-leaf-frame-pointer"
CXXFLAGS="${CFLAGS} -fvisibility-inlines-hidden"

