Which video card am I on?

[netcomrade]

I bought the T500 a few month back, but never really paid attention to the video card, as it's almost always plugged in.
Going on a long trip, and want to watch some divx files, wihch I am sure the motherboard video card would be enough for.
I am suspecting I am on secondary video card, as when i unplugged power, it estimated 2 hours of battery, and 3.5 on battery with 'maximum battery'.
I believe these laptops should last 4-5.
There is a little ATI icon on the bottom, which i expected to be the tool to switch between cards, but it doesn't appear to be so (says radeon HD 3650)
Anyway.. where do I look/check/switch?
OS is XP SP3

Thanks in advance.

[ZaZ]

If you're running XP it has to be switched in the BIOS. If you're running Vista you can do it right in Vista.