CHAINTECH 9CJS User Manual page 10

The following conditions must be met:
–Matched DIMM configuration in each channel
•Same Density (128MB, 256MB, 512MB, etc.)
•Same DRAM technology (128Mb, 256Mb, or 512Mb)
•Same DRAM bus width (x8 or x16)
•Both either single-sided or dual-sided
–Matched in both Channel A and Channel B memory channels
•Populate symmetrical memory slots (Slot 0 or Slot 1)
The following conditions do not need to be met:
–Same brand
–Same timing specifications
–Same DDR speed
Symmetrical DIMMs must be identical for optimal performance
–Same DIMM density, eg 128MB, 256MB, 512MB, etc.
–Same DRAM Technology, eg 128M-bit, 256M-bit, etc.
–Same DRAM bus width, eg x8 or x16
–Single Sided or Dual Sided
Note: Memory interface speed will be set to lowest speed of memory populated
Memory Characteristics
Optimize performance for single or dual channel is obtained with matched DIMM
population
Table below shows DIMMs with same Organization and Density, but are non-matching as
bus width, technology and/or external banks are different
–Mixing these DIMMs will put platform into single channel mode
Chapter 2
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Chapter 2
Maximizing Performance
Optimal configurations for highest performance:
–Matched, DDR400, Double-sided DIMMs
–Dual Channel Mode (Symmetrical DIMM population)
–Matched, DDR400, Dual Channel Mode
When not using DDR400, highest performing configuration:
–Symmetrical DIMM population with matched double-sided DIMMs
–Lightly loaded memory population aids in higher performance
–x8 Bus Width and lower DIMM cache latency also assists in higher performance
Dual Channel memory configuration provides higher performance than Single
Channel configurations
Matched DIMMs need to have identical density, DRAM technology, DRAM bus
width, and equal number of memory banks
Optimal platform performance with Dual Channel, DDR400, matched DIMMs
– Fully loaded configurations can be single or double sided DIMMs
– Lightly loaded configurations need to be double sided DIMMs
When not using DDR400, best performance obtained with
– Symmetrical DIMM population and matched double-sided DIMMs
– Lightly loaded configuration
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