You didn't really answer my question. Are you using dual view or horizontal span? The search engine is your friend..

One computer five boxing tips, suggestions.

[Keyclone] Maximizing FPS with Maximizer? Issues with very low FPS

Dual boxing 1 computer 2 monitors

Improving Frame Rate (ATI Card)

et al ad nauseam

EDIT: Arrrrgh Grammar has walked the plank matey!

EDIT2: So did spelling!