Microsoft System Board manual Memory Hole At 15M-16M, PCI 2.1 Compliance, AGP Aperture Size MB

!Award BIOS Setup Utility

Memory Hole At 15M-16M

In order to improve system performance, certain space in memory can be reserved for ISA cards. This memory must be mapped into the memory space below 16MB. When enabled, the CPU assumes the 15-16MB memory range is allocated to the hidden ISA address range instead of the actual system DRAM. When disabled, the CPU assumes the 15-16MB address range actually contains DRAM memory. If more than 16MB of system memory is installed, this option must be disabled to provide contiguous system memory.

PCI 2.1 Compliance

By default, this field is Disabled. However, if you encounter problems with your PCI card, try setting this field to Enabled. It may be that your card is PCI 2.1 compliant.

AGP Aperture Size (MB)

This field is relevant to the memory-mapped graphics data of the AGP card installed in your system. Leave this in its default setting, which is 64MB.

CPU/PCI Clock (MHz)

This field is used to select the external system bus clock of your processor. The options are Default, 66.8/33.4, 75/37.5, 83.3/ 41.65, 100.3/33.4, 103/34.33, 105/35, 110/36.67, 112/37.33, 115/38.33, 120/40, 124/31, 124/41.33, 133/33.25, 133/44.33, 140/35 and 150/37.5. When selecting the external bus clock of your processor, the PCI clock will at the same time appear next to the external bus clock selected. For example, if you selected “66.8/ 33.4”, 66.8MHz is the external bus clock and 33.4MHz is the PCI clock. Regardless of the type of processor used, the default setting is “Default”. Under this setting, the system will run according to the processor’s clock frequency. If you selected an option other than “Default” and is unable to boot up the system, there are 2 methods of going back to its default setting.

Method 1:

Clear the CMOS data by following the procedure in section 2.5 (chapter 2) of this manual. All fields in the BIOS Setup will automatically be set to its default settings.

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