Advantech PCA-6186 User Manual

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PCA-6186 User’s Manual
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3.5.4 DRAM RAS# to CAS#  Delay
In order to improve performance, certain space in memory is reserved for 
ISA cards. This memory must be mapped into the memory space below 
16MB. The Choice: 15M-16M, Disabled. 
3.5.5 RAS# Precharge Time
This controls the idle clocks after issuing a precharge command to 
DRAM. Leave this on the default setting.
3.5.6 System BIOS Cacheable
Selecting Enabled allows caching of the system BIOS ROM at F0000h-
FFFFFh, resulting in better system performance. However, if any pro-
gram writes to this memory area, a system error may occur. The Choices: 
Enabled, Disabled.
3.5.7 Video Bios Cacheable
Selecting Enabled allows caching of the video BIOS, resulting in better 
system performance. However, if any program writes to this memory 
area, a system error may occur. The Choices: Enabled, Disabled.
3.5.8 Memory Hole At 15M-16M
Enabling this feature reserves 15 MB to 16 MB memory address space 
for ISA expansion cards that specifically require this setting. This makes 
memory from 15 MB and up unavailable to the system. Expansion cards 
can only access memory up to 16 MB. The default setting is “Disabled.”
3.5.9 Delayed Transaction
The chipset has an embedded 32-bit posted write buffer to support delay 
transactions cycles. Select Enabled to support compliance with PCI spec-
ification version 2.1. The Choice: Enabled, Disabled.
3.5.10 Delay Prior to Thermal
Select Enabled if user wants to lower the CPU speed when CPU tempera-
ture is too high.   The choice: Enabled, Disabled.
3.5.11 AGP Aperture Size (MB)
Select the size of Accelerated Graphics Port (AGP) aperture.  The aper-
ture is a portion of the PCI memory address range dedicated for graphics 
memory address space.  Host cycles that hit the aperture range are for-
warded to the AGP without any translation. 
3.5.12 On-Chip VGA
User can disable onboard VGA controller by selecting "Disabled"