Question 1

Install fails or rolls back?

Accepted Answer

Legacy SiS 6326 drivers are often unsigned or block on newer Windows. Run the installer as administrator in compatibility mode for the target OS; if needed, temporarily disable driver signature enforcement and install manually via Device Manager > Update driver > Browse > Have Disk, selecting the correct SiS 6326 INF.

Question 2

Device not detected?

Accepted Answer

Check that the card is fully seated and, for AGP, that the motherboard BIOS has AGP enabled with a valid aperture size. Install chipset/AGP drivers first. In Device Manager, look for an unknown VGA device with hardware ID `VEN_1039` and `DEV_6326`; if absent, reseat the card or test another slot.

Question 3

Version conflicts / wrong driver loaded?

Accepted Answer

Remove any existing SiS or generic display driver before installing. Use Device Manager to uninstall the current display adapter, reboot, then install the matching PCI or AGP package. Prevent Windows Update from silently replacing it afterward.

SiS 6326 PCI/AGP Driver