MSI 845 Ultra Manual page 60

to be allowed to precharge. If insufficient time is allowed for the RAS to
accumulate its charge before DRAM refresh, refresh may be incomplete
and DRAM may fail to retain data. This item applies only when synchro-
nous DRAM is installed in the system. Setting options: 2 Clocks, 3 Clocks.
RAS# to CAS# Delay
When DRAM is refreshed, both rows and columns are addressed
separately. This setup item allows you to determine the timing of the
transition from RAS (row address strobe) to CAS (column address strobe).
The less the clock cycles, the faster the DRAM performance. Setting
options: 3 Clocks, 2 Clocks.
Precharge Delay
This setting controls the precharge delay, which determines the timing
delay for DRAM precharge. Setting options: 5 Clocks, 6 Clocks, 7 Clocks.
DRAM Integrity Mode
Select ECC (Error-Checking & Correcting Code) or Non-ECC according to the
type of DRAM installed.
Memory Hole
In order to improve performance, certain space in memory can be reserved for
ISA cards. This memory must be mapped into the memory space below 16MB.
When this area is reserved, it cannot be cached. Setting options: Disabled,
15MB-16MB.
AGP Aperture Size
The field selects the size of the Accelerated Graphics Port (AGP) aperture.
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. Settings: 4MB, 8MB, 16MB, 32MB, 64MB,
128MB, 256MB.
Delayed Transaction
The chipset has an embedded 32-bit posted write buffer to support delayed
transactions cycles. Select Enabled to support compliance with PCI specifica-
tion version 2.1. Settings: Enabled and Disabled.
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BIOS Setup