总结：服务器现在有14G内存，由 4 个插槽（2G+2G+2G+8G）因为它在一个插槽中有一个最大内存8G，为什么最大容量是16G，而不是8*4=32G
详细信息如下：
klg@gentoo:~$ 免费 -m
total used free shared buffers cached
Mem: 14022 12270 1751 0 45 7189
klg@gentoo:~$ sudo dmidecode -t 17 [sudo] klg 的密码：
# dmidecode 2.11
SMBIOS 2.6 present.
Handle 0x1100, DMI type 17, 28 bytes
Memory Device
Array Handle: 0x1000
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: 1
Locator: DIMM_A1
Bank Locator: Not Specified
Type: DDR3
Type Detail: Synchronous Unbuffered (Unregistered)
Speed: 1333 MHz
Manufacturer: 019800000000
Serial Number: 5D3BFD38
Asset Tag: 04105200
Part Number: 9965413-011.A00LF
Rank: 2
Handle 0x1101, DMI type 17, 28 bytes
Memory Device
Array Handle: 0x1000
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 8192 MB
Form Factor: DIMM
Set: 1
Locator: DIMM_A2
Bank Locator: Not Specified
Type: DDR3
Type Detail: Synchronous Unbuffered (Unregistered)
Speed: 1600 MHz
Manufacturer: 019800000000
Serial Number: F72AA08D
Asset Tag: 04144700
Part Number: 9965525-116.A00LF
Rank: 2
Handle 0x1102, DMI type 17, 28 bytes
Memory Device
Array Handle: 0x1000
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: 2
Locator: DIMM_A3
Bank Locator: Not Specified
Type: DDR3
Type Detail: Synchronous Unbuffered (Unregistered)
Speed: 1333 MHz
Manufacturer: 019800000000
Serial Number: 5E3B4C08
Asset Tag: 04105200
Part Number: 9965413-011.A00LF
Rank: 2
Handle 0x1103, DMI type 17, 28 bytes
Memory Device
Array Handle: 0x1000
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: 2
Locator: DIMM_A4
Bank Locator: Not Specified
Type: DDR3
Type Detail: Synchronous Unbuffered (Unregistered)
Speed: 1333 MHz
Manufacturer: 019800000000
Serial Number: 6D3ACDE3
Asset Tag: 04105200
Part Number: 9965413-011.A00LF
Rank: 2
更新：使用DELL R210 http://www.dell.com/downloads/global/products/pedge/en/PowerEdgeR210TechGuide_04052010.pdf 阅读指南后，发现：
System Capacity|System Memory Speed|DIMM Speed|DIMM_T ECH|DIMM Capacity |NUM_DI MM|Slot|NUM_Rank|Data Width
8GB 1333 1333 UDIMM 4 2 1,2 2 X8
16GB 1066 1066 UDIMM 4 4 1,2,3,4 2 X8
** 似乎最大值应为 16Gx4=32G，频率为 1066MHZ **
klg@gentoo:~$ sudo dmidecode -t 16 [sudo] klg 的密码：# dmidecode 2.11 SMBIOS 2.6 存在。
Handle 0x1000, DMI type 16, 15 bytes
Physical Memory Array
Location: System Board Or Motherboard
Use: System Memory
Error Correction Type: Multi-bit ECC
Maximum Capacity: 16 GB
Error Information Handle: Not Provided
Number Of Devices: 4
最大容量：16 GB，好像有点奇怪。操作系统，使用ubuntu 12.04。