IEI Technology WSB-9452, Руководство пользователя

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WSB-9452 PICMG 1.0 CPU Card
Page 161
533MHz Sets the DRAM frequency to 533MHz
667MHz Sets the DRAM frequency to 667MHz
Configure DRAM Timing by SPD [Enabled]
Use the Configure DRAM Timing by SPD option to determine if the system uses the
SPD ( Serial Presence Detect) EEPROM to configure the DRAM timing. The SPD
EEPROM contains all necessary DIMM specifications including the speed of the individual
components such as CAS and bank cycle time as well as valid settings for the module and
the manufacturer's code. The SPD enables the BIOS to read the spec sheet of the DIMMs
on boot-up and then adjust the memory timing parameters accordingly.
Disabled DRAM timing parameters are manually set using the
DRAM sub-items
Enabled D
EFAULT
DRAM timing parameter are set according to the
DRAM Serial Presence Detect (SPD)
If the Configure DRAM Timing by SPD option is disabled, the following configuration
options appear.
DRAM CAS# Latency [5]
DRAM RAS# to CAS# Delay [6 DRAM Clocks]
DRAM RAS# Precharge [6 DRAM Clocks]
DRAM RAS# Activate to Precha [15 DRAM Clocks]
Memory Hole [Disabled]
Use the Memory Hole option to reserve memory space between 15MB and 16MB for ISA
expansion cards that require a specified area of memory to work properly. If an older ISA
expansion card is used, please refer to the documentation that came with the card to see if
it is necessary to reserve the space.