FS9 and Vista---Monitor problems

Hi allCan anyone help, I have just upgraded XP to Vista Ultimate and have a 4 monitor setup, with 2 Nvidia 7800 GTX cards on a ASUS SLI board, have a 3gb cpu and 4gb of memory.I run FS9 and FSX (not togther ) on 3 of the monitors giving a front and 2 x 45* views, the textures are fine with excellent ground detail on the front and right hand side monitor, but the left monitor textures are suffering from the blurries.I have the latest Nvidia drivers installed, and all 4 monitors are the same make. Anyone any ideas on what i am doing wrong, or is it another Vista gremlim?.Thanks Paul