Take a look at this and see if it works....
1. Click on the up arrow icon near the battery indicator located at the bottom right corner of your computer display.
2. Once you click on the up arrow it will show some hidden icons not normally displayed on your taskbar. Move your mouse around those icons until the “Energy Manager” text is displayed.
3. Click on that icon and the Energy Manager screen will show up. Then click on the small circular dialogue box located on the right hand side just above the big clock-like indicator.
4. On the top right corner click on “Settings”. On the right hand side of the Conservation Mode is a switch like gauge.
5. Move the switch from left to right with your mouse until you see an orange colored “I” appears. This shows that you have already switched on the Conservation Mode. To confirm, you will see the Conservation Mode displayed near the electrical plug icon.
6. Exit by cllicking "X" located on the top right hand corner of the dialogue box. And you're done!