XFX 5700 Ultra problem with dual display

[digitaltrader]

I recently purchased 2 dell 2001fp 20 inch lcd displays and bought the XFX 5700 ultra card with dual dvi support to manage them. I am attempting to set these two displays up using maximum resolution (1200x1600) in a shared desktop mode. However, when I try to use the monitors in potrait mode (2x 1600x1200 or 3200x2400 combined) one of the diplays flashed several lines of colored pixels. This is not a problem with the display as I have tested each display individually without problem. Is there anyway to get this card to display dual DVI output in dual portrait mode at 1600x1200 resolution x2 or is there another card I should look into? Thanks.