Video Ram Cacheable; Bit I/O Recovery Time; Memory Hole At 15Mb - 16Mb; Passive Release - TMC TI6NBF+ User Manual

Chapter 6 BIOS and System Setup

Video RAM Cacheable

Selecting Enabled allows caching of the video BIOS ROM at C0000h to
C7FFFh, resulting in better video performance. However, if any program
writes to this memory area, a memory access error may result.

8 Bit I/O Recovery Time

This option specifies the length of the delay (in sysclks) inserted between
consecutive 8-bit I/O operations. The settings are 1, 2, 3, 4, 5, 6, 7, or 8.
The default setting is 3.
16 Bit I/O Recovery Time
This option specifies the length of the delay (in sysclks) inserted between
consecutive 16-bit I/O operations. The settings are 1, 2, 3, 4, 5, 6, 7, or 8.
The default setting is 2.

Memory Hole at 15MB - 16MB

In order to improve performance, certain space in memory can be
reserved for ISA cards. This field allows you to reserve 15MB to 16MB
of memory address space to ISA expansion cards. This makes memory
from 15MB and up unavailable to the system. Expansion cards can only
access memory up to 16MB. By default, this field is set to Disabled.

Passive Release

When enabled, CPU to PCI bus accesses are allowed during passive
release. Otherwise, the arbiter only accepts another PCI master access to
local DRAM.

Delayed Transaction

The chipset has an embedded 32-bit posted write buffer to support delay
transactions cycles. Select Enabled to support compliance with PCI
specification version 2.1. The default setting is Enabled.

AGP Aperture Size (MB)

The field sets aperture size of the graphics. The aperture is a portion of
the PCI memory address range dedicated for graphics memory address
space. Host cycles that hit the aperture range are forwarded to the AGP
without any translation. The options available are 4, 8, 16, 32, 64, 128M
and 256. The default setting is 64.

Auto Detect DIMM/PCI Clk

When enabled, the system automatically shuts off clocks of unused
DIMM/PCI slots. The default setting is Disabled. This field is for CE
testing use only.
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