Laptop Monitor Dead, but drivers ignore that.

[twirp]

Okay, so I sortof have a strange problem.
I was able to install Ubuntu 8.10 on a laptop. The laptop's built in monitor is broken and no longer works.
I have an external monitor hooked up and it's working somewhat fine now, but the problem is it's stuck at a resolution of 800x600 (it's a widescreen capable of 1440x900 i think?)
The issue is when I install the Driver for the Graphics Card, the laptop loads up the GUI and everything on the built-in monitor, and I can't really see anything... I believe it has a NVIDIA GeForce4 FX Go5200 graphics card (at least that's what the product page says).

The BIOS is Phoenix BIOS ver 1.6 (I think), and I can't find a place about ignoring displays or something...

So I was wondering if there was a way to install the drivers so I could use the external monitor at a bigger screen resolution without it trying to use the built-in laptop monitor.

Thanks for any help or advice.

[twirp]

Okay, so I was able to get the driver to install, but NVida is weird and providing a 1440x900 resolution, but it only display 640x400 at a time depending on where my cursor is.
Has anyone experienced this before?