CHAINTECH 6VJD2, User Manual

Page: 21 / 51

Chapter 2
18
2-5 Main Memory Configuration
The memory system consists two DDR DIMS and two SDRAM DIMMS which can
supports the memory size up to 1GB per bank . If you only use one bank it does not
matter which one you use and if you use two banks, it does not matter which bank you
install first. If you opted to use the DDR instead of the SDRAM, a DDR terminator card
must be inserted into the DIMM2 socket. (See figures below)
DDR SDRAM Specifications
DIMM type: 3.3V, unbuffered, registered, 64/72-bit SDRAM
2.5V, Registered 64/128/256-bit DDR SDRAM
Module size: Single/double-sided 64/128/256/512MB/1GB
DRAM speed: 7.5ns for DDR/SDRAM
Parity: Either parity or non-parity
DDR
Double Data Rate transfers allows for data to be fetched on both the rising and falling
edges of the clock thus doubling the effective transfer rate of the clock. For example
a 133MHz DDR clock would achieve a peak transfer rate equal to that of a 266MHz
clock. The effective transfer rate is equal to the clock frequency multiplied by the
bus width, doubled.
FSB Frequency Internal System Bus Freq.
66 MHz 200 MHz
100 MHz 200/266 MHz
133 MHz 200/266 MHz
DDR Terminator module
Insert terminator here