Chapter 2
BIOS Setup
2-28
PCI / VGA Palette Snoop
Choose Disabled or Enabled. Some graphic controllers which are not VGA
compatible take the output from a VGA controller and map it to their display as a
way to provide boot information and VGA compatibility.
However, the color information coming from the VGA controller is drawn from
the palette table inside the VGA controller to generate the proper colors, and the
graphic controller needs to know what is in the palette of the VGA controller.
To do this, the non-VGA graphic controller watches for the Write access to the
VGA palette and registers the snoop data. In PCI based systems, where the
VGA controller is on the PCI bus and a non-VGA graphic controller is on an ISA
bus, the Write Access to the palette will not show up on the ISA bus if the PCI
VGA controller responds to the Write.
In this case, the PCI VGA controller should not respond to the Write, it should
only snoop the data and permit the access to be forwarded to the ISA bus. The
non-VGA ISA graphic controller can then snoop the data on the ISA bus.
Unless you have the above situation, you should disable this option.
Disabled
(default)
Disables the function.
Enabled
Enables the function.
