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X8DTG-DF User's Manual
Memory Support
The X8DTG-DF supports up to 96 GB of Registered ECC or up to 24 GB of Unbuf-
fered ECC/Non-ECC DDR3 1333/1066/800 MHz Memory in 12 DIMMs.
Note1: With Unbuffered ECC/Non ECC memory, maximum of 2 GB of
memory is supported per DIMM slot.
Note 2: memory speed support is dependent on the type of CPU used
on the board.
DIMM Module Population Confi guration
For memory to work properly, follow the tables below for memory installation:
DIMM Population Table
DIMM
Slots per
Channel
DIMMs
Populated
per Channel
DIMM Type (Reg.=
Registered)
Speeds (in MHz) Ranks per DIMM
(any combination;
SR=Single Rank,
DR=Dual Rank,
QR=Quad Rank)
2 1 Reg. DDR3 ECC 800,1066,1333 SR or DR
2 1 Reg. DDR3 ECC 800,1066 QR
2 2 Reg. DDR3 ECC 800,1066 Mixing SR, DR
2 2 Reg. DDR3 ECC 800 Mixing SR, DR,QR
Note 1: Due to OS limitations, some operating systems may not show
more than 4 GB of memory.
Note 2: Due to memory allocation to system devices, the amount of mem-
ory that remains available for operational use will be reduced when 4 GB
of RAM is used. The reduction in memory availability is disproportional.
Possible System Memory Allocation & Availability
System Device Size Physical Memory Available
(4 GB Total System Memory)
Firmware Hub fl ash memory (System BIOS) 1 MB 3.99 GB
Local APIC 4 KB 3.99 GB
Area Reserved for the chipset 2 MB 3.99 GB
I/O APIC (4 Kbytes) 4 KB 3.99 GB
PCI Enumeration Area 1 256 MB 3.76 GB
PCI Express (256 MB) 256 MB 3.51 GB
PCI Enumeration Area 2 (if needed) -Aligned on 256-M
boundary-
512 MB 3.01 GB
VGA Memory 16 MB 2.85 GB
TSEG 1 MB 2.84 GB
Memory available for the OS & other applications 2.84 GB
