What Are The Power Saving Options In Windows And What Do They Do?

Power management for Windows computers is handled by ACPI (Advanced Configuration and Power Interface).

There are 5 sleep states:

1. S0 Lowest Level of power saving: everything is on.
2. S1 Minimal power saving. The system is powered on, all system context is preserved.
3. S2 Normal power saving. The system is powered on but CPU and cache info is lost.
4. S3 Higher power saving. The system is powered on but all system context is lost. RAM is saved.
5. S4 Hibernate. The system is powered off. All info is saved to disk. Power can be removed.
6. S5 Off. No context saved.
   

Before you can decide what options you want to use you need to find what is available on your computer.

1. Open a command prompt window: type CMD in a rub box dialogue from the Start menu
2. Type : powercfg /availablesleepstates

Look in your BIOS for "ACPI suspend state" or something like that. If possible, choose S1/S3. Ignore any timeout settings.

Armed with this info go to Control Panel in XP and double click Power Options and choose settings that suit you for the different schemes or create your own.

OS (Windows etc)