Datacolor Spyder3 Elite Help Manual page 85

Information will then be distributed out to all of the computers indicating the target
settings that they should use. Then the calibration process will be run on every
computer to adjust their displays to matching settings.
Note: Multiple Monitors
Computers using the Windows operating system with multiple displays may need to
have a separate video card for each display. Multi-head video cards (a single card that
drives two or more displays) that are not PCI Express cards often are not capable of
holding unique calibrations for multiple displays. Each display must have its own
profile, created specifically for that display, associated with it. Associating different
profiles to displays attached using a multi-head video card may not function correctly
under Windows.
Computers using the Macintosh operating system do not have this issue. There is no
problem using multi-head video cards on Macintosh.
Further Information
For information such as a list of Frequently Asked Questions and details on all
Datacolor products be sure to visit our website: www.datacolor.com/Spyder3