The combined effects of chromatic dispersion, self-phase modulation and laser chirp are numerically investigated for a 10 Gbit/s IM-DD system over 100 km of standard single-mode fiber. Fiber based pre- and post-compensation of the chromatic dispersion is compared. The results show that partial post-compensation of the chromatic dispersion yields low eye opening penalty and the penalty is power independent over a very wide power range.