* Cut down external devices - USB devices (including your mouse) & WiFi drain down you laptop battery.

* Remove or shut them down when not in use. It goes without saying that charging other devices (like your iPod) with your laptop when on battery is a surefire way of quickly wiping out the charge on your laptop battery.

* Keep the battery contacts clean: Clean your battery's metal contacts every couple of months with a cloth moistened with rubbing alcohol. This keeps the transfer of power from your battery more efficient.

* Hibernate not standby - Although placing a laptop in standby mode saves some power and you can instantly resume where you left off, it doesn't save anywhere as much power as the hibernate function does. Hibernating a PC will actually save your PC's state as it is, and completely shut itself down.

* Turn off the autosave function MS-Word's and Excel's autosave functions are great but because they keep saving regular intervals, they work your hard driver harder than it may have to. If you plan to do this, you may want to turn it back on as the battery runs low. While it saves battery life in the beginning, you will want to make sure your work is saved when your sony pcga-bp505 battery battery dies.

* the autosave tip probably has very little effect though and leaves you exposed if you forget to turn it back on.

* if you use a screensaver, put it on "blank", other screensavers can eat CPU time and hence power

* Go into power profiles and put Hibernate on the power button

* Set your power settings for as short a time for sleep and hibernate as you can put up with

* Naturally, keep the screen as dim as you can. Use the "Fn" button on most laptops in conjunction with the little sunshine icons to manually raise or drop the backight Battery Use Factors There are a number of factors that contribute to or determine the usable laptop ac adapter time for your laptop.

* Display brightness.

* USB Devices drawing power (such as iPODs).

* Use of hard drive.

* Use of optical (CD/DVD) drive.

* Battery charge state (was it fully charged).

* Battery age - batteries have a finite life span.

* Network use.

* Memory upgrades - more memory means more power use.