An update to the Monitors control panel resolves an issue with some third party video cards which revert to the black and white setting upon restart. Upgrade to version 7.3.2 or later to resolve this problem. This version was first shipped as part of the Display Software 1.0 which shipped with the Apple Multiple Scan 17 and 20 displays.
System Software versions greater than 7.1.2 also includes a version of the Monitors control panel that resolves this problem.
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