On your video card there's a flash memory called "look up table" (LUT). The SpyderUtility.exe flashes correction data to the LUT. This is a big part of your color management.
When your computer is switched to the power save mode, there's no power on the LUT and the flash memory looses the data.
The best solution should be to switch off the power save mode. Then you will keep the monitor warm and you will get the best colors.