MSI 865PE NEO3-F User Guide - Page 51

RAS# Precharge, Precharge Delay, Burst Length, AGP Aperture Size MB, Internal Graphics Select

Page 51 highlights

BIOS Setup RAS# Precharge This item controls the number of cycles for Row Address Strobe (RAS) to be allowed to precharge. If insufficient time is allowed for the RAS to accumulate its charge before DRAM refresh, refreshing may be incomplete and DRAM may fail to retain data. This item applies only when synchronous DRAM is installed in the system. Available settings: [2 clocks], [3 clocks], [4 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: [2 clocks], [3 clocks], [4 clocks]. Precharge Delay This setting controls the precharge delay, which determines the timing delay for DRAM precharge. Settings: [5 clocks], [6 clocks], [7 clocks], [8 clocks]. Burst Length This setting allows you to set the size of Burst-Length for DRAM. Bursting feature is a technique that DRAM itself predicts the address of the next memory location to be accessed after the first address is accessed. To use the feature, you need to define the burst length, which is the actual length of burst plus the starting address and allows internal address counter to properly generate the next memory location. The bigger the size, the faster the DRAM performance. Available settings: [4], [8]. AGP Aperture Size (MB) This setting controls just how much system RAM can be allocated to AGP for video purposes. The aperture is a portion of the PCI memory address range dedicated to graphics memory address space. Host cycles that hit the aperture range are forwarded to the AGP without any translation. The option allows the selection of an aperture size of [4MB], [8MB], [16MB], [32MB], [64MB], [128MB], and [256 MB]. Internal Graphics Select The field specifies the size of system memory allocated for video memory. Settings: [512KB], [1MB], [8MB], [Disabled]. 3-13

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3-13
BIOS Setup
RAS# Precharge
This item controls the number of cycles for Row Address Strobe (RAS) to be allowed
to precharge. If insufficient time is allowed for the RAS to accumulate its charge
before DRAM refresh, refreshing may be incomplete and DRAM may fail to retain
data. This item applies only when synchronous DRAM is installed in the system.
Available settings: [2 clocks], [3 clocks], [4 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: [2 clocks], [3 clocks], [4 clocks].
Precharge Delay
This setting controls the precharge delay, which determines the timing delay for
DRAM precharge. Settings: [5 clocks], [6 clocks], [7 clocks], [8 clocks].
Burst Length
This setting allows you to set the size of Burst-Length for DRAM. Bursting feature is
a technique that DRAM itself predicts the address of the next memory location to be
accessed after the first address is accessed. To use the feature, you need to define
the burst length, which is the actual length of burst plus the starting address and
allows internal address counter to properly generate the next memory location. The
bigger the size, the faster the DRAM performance. Available settings: [4], [8].
AGP Aperture Size (MB)
This setting controls just how much system RAM can be allocated to AGP for video
purposes. The aperture is a portion of the PCI memory address range dedicated to
graphics memory address space. Host cycles that hit the aperture range are for-
warded to the AGP without any translation. The option allows the selection of an
aperture size of [4MB], [8MB], [16MB], [32MB], [64MB], [128MB], and [256 MB].
Internal Graphics Select
The field specifies the size of system memory allocated for video memory. Settings:
[512KB], [1MB], [8MB], [Disabled].