update Nvidia GeForce 6150LE video driver

I installed Ubuntu 9.10 on an Asus A8N-LA MoBo which has an Nvidia GeForce 6150LE onboard video chipset. The default installation would not run the screen resolution any higher than 800x600, so I looked to update the video driver. I found instructions involving "sudo add-apt-repository ppa:nvidia-vdpau/ppa" followed by "sudo apt-get update", which I did; but after it downloaded all the updates and restarted, the video resolution still won't go any higher. I have no clue what to do further; being a Windows user, I'm looking for a hardware Device Manager that shows the driver version with an option to update but I can't find such a thing. I'd appreciate some help! - JR