Chapter 5: Advanced Serverboard Setup

5-9

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

Notes: Due to OS limitations, some operating systems may not show more than

4 GB of memory.

Due to memory allocation to system devices, the amount of memory that remains

available for operational use will be reduced when 4 GB of RAM is used. The reduc-

tion in memory availability is disproportional. See chart below.

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