Battery runs low way too fast

[friendly2004]

Hey folks

I am running Ubuntu 9.04 on my HP NX6125.

After I had gotten rid of Windows XP I installed Ubuntu 8.04 or 8.10 (can't remember). And when prompted I accepted to update.

Now my battery only lasts for about 30 minutes in normal use: email and internet via wifi.

Can this have something to with the lack of support for my proprietary graphics driver? I was warned before installing the update that fglrx and stuff would not be available.

Appreciate your efforts.

Thanks