Hi Jirka, A quick Google search indicates that the Pentium 4 does not natively support 128-bit floating point arithmetic. It does support 64-bit precision mantissa, which would (I presume) be utilized in full via long double (80-bit on Intel architecture, 96-bit on Motorolla 680x0 architecture). Unless I'm mistaken, to use 128-bit floating point, you'll need to write your own "software FPU" or download a floating point bignum to suite your needs. Chongo's calc software can do that at even higher precision, and more <http://freshmeat.net/projects/calc/>... mind the licensing restrictions. Performance will be far less than that of the Pentium 4's FPU, however. HTH, --Eljay
