NEC PowerMate Pro150 Series Service Manual page 63

2-26 Setup and Operation
This "Disabled" setting should not be changed unless you are using an ISA board which 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.
n
Disabled (default)
n
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 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 are occur.
n
An ISA card connects to a PCI Graphics card via the VESA connector
n
The ISA card connects to a color monitor
n
The card uses the RAMDAC on the PCI card
n
The palette snooping feature is broken on the PCI card
Latency Timer (PCI Clocks)
The Latency Timer (PCI CLOCKS) field controls the length of time an agent on the PCI
bus can hold the bus when another agent has requested the bus. Value choices range
between 0 and 256, the default value is 66.
In general this should not be changed. If there are latency sensitive cards in the system (such
as audio cards and/or network cards with small buffers) this can be set to a lower value to
reduce latency.
If there are no latency sensitive cards in the system, but I/O intensive applications are being
run, this can be increased to slightly improved performance.
PCI Burst
Disable PCI Burst when installing slower PCI video cards. The default is "Enabled".