You need to colorsync your monitors again. System Preferences -> Displays -> Color
Try one of the existing profiles listed, or click the Calibrate button.
Alternatively, if you'd calibrated before, you can copy your custom profiles across - if you still have your old install. If you really did do a clean install instead of an Archive Install, then the custom profiles will be gone.
If you can still reach your old root Library folder, the custom profiles are located at:
/Library/ColorSync/Profiles/Displays/name_of_profile.icc
You would copy the file(s) across to the same location in your Tiger install, and they will become available in the Color tab.