4. BIOS SETUP

SDRAM Cycle Time tRAS [7T]

This feature controls the number of SDRAM clocks used for SDRAM parameter tRAS. tRAS specifies the minimum clocks required between active command and precharge command. NOTE: To make changes to this field, set the SDRAM Configuration field to [User Defined].

Graphics Aperture Size [128MB]

This feature allows you to select the size of mapped memory for AGP graphic data. Configuration options: [1MB] [4MB] [8MB] [16MB] [32MB] [64MB] [128MB] [256MB]

AGP Capability [4X Mode]

This motherboard supports the AGP 4x interface that transfers video data at 1066MB/s. AGP 4x is backward-compatible, so you may leave the default [4X Mode] on even if you are using an AGP 1x or 2x video card. When set to [1X Mode], the AGP interface only provides a peak data throughput of 266MB/s even if you are using an AGP 2x/4x card. When set to [2X Mode], the AGP interface only provides a peak data throughput of 533MB/s even if you are using an AGP 4x card. Configuration options: [1X Mode] [2X Mode] [4X Mode]

Video Memory Cache Mode [UC]

USWC (uncacheable, speculative write combining) is a new cache technology for the video memory of the processor. It can greatly improve the display speed by caching the display data. You must set this to UC (uncacheable) if your display card does not support this feature, otherwise the system may not boot. Configuration options: [UC] [USWC]

Memory Hole At 15M-16M [Disabled]

This field allows you to reserve an address space for ISA expansion cards. Setting the address space to a particular setting makes that memory space unavailable to other system components. Expansion cards can only access memory up to 16MB. Configuration options: [Disabled] [Enabled]

PCI 2.1 Latency Compliant [Disabled]

This field allows you to enable or disable the PCI 2.1 latency compliant mode for the primary bus. Configuration options: [Disabled] [Enabled]

Delay Transaction [Disabled]

When set to [Enabled], this feature frees the PCI bus when the CPU is accessing 8-bit ISA cards. This process normally consumes about 50-60 PCI Clocks without PCI delayed transaction. Set this field to [Disabled] when using ISA cards that are not PCI 2.1 compliant. Configuration options: [Enabled] [Disabled]

Chip Configuration

4. BIOS SETUP

ASUS CUA266 User’s Manual

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