Intel Socket 478 AIMB-744 - Manual (Page 28)

AIMB-744 User’s Manual 14
1.8.5 PCI-X slots 3.3V/5V selection (J8)
The AIMB-744 contains a PCI-X 3.3V/5V selection that provide the user
to select the operation voltage either 3.3V or 5V. The default setting is
3.3V which close pin1 and pin2. By closing pin2 and pin3, the operation
voltage change to 5V.
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.
Table 1.6: PCI-X slots 3.3V/5V selection (J8)
Function Jumper Setting
*3.3V
5V
Table 1.7: CPU FSB and memory speed
1-2 Closed
2-3 Closed