I get significantly poorer results encoding .avi files under XP, than under 98SE or ME.

This using the same avi file, same TMPGEnc12 configuration settings, but encoding on different systems.

P2-400 for 98SE, P3-866 for ME, and P3-1.13 Mobile (laptop) for XP.
All are linked in a LAN.

Do I need to encode on the slower systems -- to achieve near DVD quality results, forsaking the faster XP system?

Is there something I am missing?

Any help is appreciated.