Hi, I have a 27" Planar monitor hooked up to my Macbook Pro (via HDMI), but it doesn't look as crisp as my laptop's screen. I'm not sure if it's a resolution issue or what. The MBP's max resolution is 1440x900. Monitor's max resolution is 1920x1080. What can I do to make the external monitor look sharper? Change Underscan?When I go into System Preferences of Display, there isn't a selection for MBP's 1440x900 for the external monitor. The ext. monitor is currently running on 1080p.