Chapter 2 AMIBIOS Setup
47
Chipset Setup,
Continued
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, 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. Most DRAM errors are soft errors. 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) is enabled. 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
timeout options as desired.
Cont’d