Advantech AIMB-744 Series, User Manual

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1.9 System Memory
The AIMB-744 has four sockets for 184-pin dual inline memory modules
(DIMMs) in two separated memory channels. It can operate with single
channel or dual channel modules. We recommend to use dual channel
mode to provide optimized performance.
All these sockets use 2.5 V unbuffered double data rate synchronous
DRAMs (DDR SDRAM). They are available in capacities of 128, 256,
512 and 1024 MB. The sockets can be filled in any combination with
DIMMs of any size, giving a total memory size between 128 MB and 4
GB.
Note: System resources such as PCI and AGP cards require phys-
ical memory address locations that reduce available memory
addresses above 3GB. This may result in less than 4GB of mem-
ory being available to the operating system and applications.
1.9.1 CPU FSB and memory speed
The AIMB-744 can accept DDR SDRAM memory chips without parity.
Also note: The AIMB-744 accepts PC2100 (DDR266), PC2700 (DDR
333) and PC3200 (DDR 400) DDR SDRAM, depending on the CPU
front side bus frequency (FSB). Please refer below table for the relation-
ship between the CPU FSB and memory speed.
The AIMB-744 does not support ECC (error checking and correction).
Memory modules with 9 SDRAM chips/side support ECC; modules with
8 chips/side do not support ECC.
Table 1.8: CPU FSB and memory speed
Memory
Speed Processor FSB frequency Memory speed Outcome
DDR400 Pentium 4 800 MHz 400 MHz
DDR333 Pentium 4 800 MHz 320 MHz
Pentium 4 533MHz 333 MHz
Pentium 4
or Celeron 400 MHz 266 MHz
DDR266 Pentium 4 533 or 400 MHz 266 MHz
Celeron 400 MHz 266 MHz