Sony VGN-FS550 - Manual (Page 24)

Using the Battery
Your computer, depending on the model you purchased, may come equipped with one battery bay and one multipurpose
bay that supports a second battery. If your computer comes with two bays, you can purchase a second rechargeable
battery to extend your computing time. For information on how to extend the life of the battery, see
Conserving Battery
Power for more information.
When operating your computer on battery power, your computer's CPU speed is reduced.
The battery that comes with your computer is not fully charged at the time of purchase.
Some VAIO personal computers may function only with a genuine Sony battery.
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