When you utilize two PCI-E cards what happens is resource swapping. Basically while the 9800 is using a resource the other card is on standby. Even though this happens really quick it will wreck your FPS. Buy a spliiter and run all three monitors off the 9800 and you will see your FPS go up. Use keyclone to set your min and max fps on each window and turn down your slaves to min video settings using the WoW interface.