NEC Drivers and Utilities 4-19
640 KB (default)
−
directs address mapping between
512 KB and 640 KB to the system DRAM. Unless using
an ISA expansion board that requires access to this
address range, this field should not be changed.
ISA LFB Size
The ISA Video Linear Frame Buffer (LFB) Size provides a
mechanism for creating a hole in the system memory map.
Address accesses made to this hole will be directed to the
ISA bus instead of main memory.
This “Disabled” setting should not be changed unless you
are using an ISA board that has memory greater than 64K,
needs to be accessed by the CPU, and you are not using the
Plug and Play run-time utilities. The following choices are
available.
Disabled (default)
1 MB
ISA LFB Base Address
This field cannot be entered; it is an information field only.
If the ISA LFB field is “Disabled,” this field does not
appear.
The ISA Video LFB Base Address field displays “15 MB”
(the starting address of the ISA memory hole) if “1 MB” is
chosen as the ISA LFB Size parameter.
Video Palette Snoop
The Video Palette Snoop field enables card “snoop” (also
called RAMDAC shadowing) write cycles to the ISA video
card’s palette registers. This field can be either “Enabled”
or “Disabled;” the default is “Disabled.”
This should only be set to “Enabled” if all of the following
conditions occur.
