HP Compaq NC6220 Hardware And Software Manual page 56

To fully discharge a battery pack:
1. Select the Power Meter icon in the notification area.
– or –
Access the Power Schemes tab by selecting Start > Control
Panel > Performance and Maintenance > Power
Options > Power Schemes tab.
2. Make a note of the 2 settings in the Plugged In column and
the 2 settings in the Running on Batteries column so that
you can reset them after the calibration.
3. Use the drop-down lists to set the 4 options (2 in each
column) to Never.
4. Select OK.
5. Disconnect the notebook from the external power source, but
do not turn off the notebook.
6. Run the notebook on battery power until the battery pack is
fully discharged. The battery light begins to blink when the
battery pack has discharged to a low-battery condition. When
the battery pack is fully discharged, the battery light is turned
off and the notebook shuts down.
Hardware and Software Guide
Power
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