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Chapter 4
RAS Precharge
This option specifies the length of the RAS precharge part of the
DRAM system memory access cycle when EDO DRAM system
memory is installed in this computer. The settings are 3 CLKs or 4
CLKs. The Optimal and Fail-Safe default settings are 4 CLKs.
VGA Frame Buffer USWC
Set this option to Enabled to enable the VGA video frame buffer using
USWC (Uncacheable, Speculatable, Write-Combined) memory. The
settings are Enabled or Disabled. Older ISA VGA card drivers may not
behave correctly if this option is not set to Disabled. The Optimal and
Fail-Safe default settings are Disabled.
PCI Frame Buffer USWC
Set this option to Enabled to enable the USWC memory attribute and
improve video performance when a PCI video adapter is installed.
However, some VGA card drivers may not behave correctly when this
option is set to Enabled. The settings are Disabled or Enabled. The
Optimal and Fail-Safe defaults are Disabled.
DRAM Integrity Mode
This option sets the type of system memory checking. The settings are:
Setting
Description
Non ECC
No error checking or error reporting is done.
ECC Only
Multibit errors are detected and reported as parity errors. Single-bit errors are
corrected by the chipset. Corrected bits of data from memory are not written back to
DRAM system memory. If
Level I
is selected, the J25 External SMI software jumper
on the Series 745 board is disabled.
ECC
Multibit errors are detected and reported as parity errors. Single bit errors are corrected
by the chipset and are written back to DRAM system memory. If a soft (correctable)
memory error occurs, writing the fixed data back to DRAM system memory will resolve
the problem. If a hard (uncorrectable) error occurs, writing the fixed data back to
DRAM system memory does not solve the problem. In this case, the second time the
error occurs in the same location, a parity error is reported, indicating an uncorrectable
error. If
ECCI
is selected, AMIBIOS automatically enables the System Management
Interface (SMI). If you do not want to enable power management, set the Power
Management/APM option to
Disabled
and set all Power Management Setup timeout
options to
Disabled
. To enable power management, set Power Management/APM to
Enabled
and set the Power Management Setup timeout options as desired.
