Can Someone Please Help me with Installation of GeForce4 MX440?? Please Everyone Help

[inammiei]

I purchase my computer from an online company...so the only thing i kno about the motherboard is what they post, "810XP 266Mhz FSB AMD Athlon". I've been trying to install a new GeForce4 MX440 but have been unsuccessful. The motherboard has a built in video card. I think that may be the reason why, but when i follow the instructions on installing a new card by deleting the old drivers, shut down the computer, install hardware....it seems as though the drivers reinstall themselves or something, but the new card isnt even detected. I dont think there is anything wrong the the card or my motherboard but im still uncertain of whats wrong. My BIOS doesn't seem to give me an option of disabling the built-in video card so I have no idea what to do. Whenever I install the hardware and boot up...the Add Hardware Wizard doesn't even come up, Does anyone know what i can do or know what to do?

I don't see anything that indicates an option for disabling the onboard agp. The only thing I know about the motherboard is this:

Mainboard
200/266 Mhz AMD Athlon Front Side Bus
Supports Advanced Configuration and Power Management Interface (ACPI)
2 168-pin DIMM sockets
Plug and Play BIOS
1 4X AGP Slot
2 PCI Slots
1 Floppy Port (up to 2.88MB)
2 IDE Ports supporting up to four Ultra DMA 33/66/100 devices
1 Parallel Port (EPP/ECP)
1 Serial Port
2 USB Connectors
2 PS/2 Ports

Graphic Card
64MB Sis Display Adapter
Embeded Sis VGA
128-bit 3D AGP Graphics Accelerator
64MB frame buffer in North bridge
Upto 1920 X 1440 Resolution

I believe it means a built in ...