Why the [Expansion] option found in the [Advanced Display Properties] screen was reset to enabled after the computer restart ?

Why the [Expansion] option found in the [Advanced Display Properties] screen was reset to enabled after the computer restart ?

Re-production procedure:
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1) Click [Start] -> [Settings] -> [Control Panel] and double-click at the [Display] icon.
2) In the [Display Properties] screen, select the [Settings] tab and click at the [Advanced] button.
3) In the [Advanced Display Properties] screen, select [NeoMagic] tab and unchecked the [Expansion] option.
4) Click [OK] twice and restart computer.
5) After restart the computer, go the [Expansion] setting by steps 1 to 3 above.

The [Expansion] option of the [Advanced Display Settings] can be changed by pressing [Fn] + [F] key at the same time. Pressing the two keys again will toggle back to the original screen size. Also by using this combination the expansion mode is maintained when the computer is rebooted.

Note: The key combination is only useful when the LCD resolutions is less than 1024x768.