Ubuntu에서 내가 설치한 모든 메모리가 표시되지 않는 이유는 무엇입니까?

Ubuntu에서 내가 설치한 모든 메모리가 표시되지 않는 이유는 무엇입니까?

어떻게:

$ sudo dmidecode -t memory
[sudo] password for dims:
# dmidecode 2.12
SMBIOS 2.6 present.

Handle 0x0008, DMI type 6, 12 bytes
Memory Module Information
        Socket Designation: DIMM0
        Bank Connections: 0 1
        Current Speed: Unknown
        Type: DIMM SDRAM
        Installed Size: 2048 MB (Double-bank Connection)
        Enabled Size: 2048 MB (Double-bank Connection)
        Error Status: OK

Handle 0x0009, DMI type 6, 12 bytes
Memory Module Information
        Socket Designation: DIMM1
        Bank Connections: 2 3
        Current Speed: Unknown
        Type: DIMM SDRAM
        Installed Size: 4096 MB (Double-bank Connection)
        Enabled Size: 4096 MB (Double-bank Connection)
        Error Status: OK

Handle 0x000A, DMI type 6, 12 bytes
Memory Module Information
        Socket Designation: DIMM2
        Bank Connections: 4 5
        Current Speed: Unknown
        Type: DIMM SDRAM
        Installed Size: 2048 MB (Double-bank Connection)
        Enabled Size: 2048 MB (Double-bank Connection)
        Error Status: OK

Handle 0x000B, DMI type 6, 12 bytes
Memory Module Information
        Socket Designation: DIMM3
        Bank Connections: 6 7
        Current Speed: Unknown
        Type: DIMM SDRAM
        Installed Size: 4096 MB (Double-bank Connection)
        Enabled Size: 4096 MB (Double-bank Connection)
        Error Status: OK

Handle 0x0030, DMI type 16, 15 bytes
Physical Memory Array
        Location: System Board Or Motherboard
        Use: System Memory
        Error Correction Type: None
        Maximum Capacity: 16 GB
        Error Information Handle: Not Provided
        Number Of Devices: 4

Handle 0x0032, DMI type 17, 28 bytes
Memory Device
        Array Handle: 0x0030
        Error Information Handle: Not Provided
        Total Width: 64 bits
        Data Width: 64 bits
        Size: 2048 MB
        Form Factor: DIMM
        Set: None
        Locator: DIMM0
        Bank Locator: BANK0
        Type: DDR
        Type Detail: Synchronous
        Speed: 1333 MHz
        Manufacturer: Manufacturer0
        Serial Number: SerNum0
        Asset Tag: AssetTagNum0
        Part Number: PartNum0
        Rank: Unknown

Handle 0x0034, DMI type 17, 28 bytes
Memory Device
        Array Handle: 0x0030
        Error Information Handle: Not Provided
        Total Width: 64 bits
        Data Width: 64 bits
        Size: 4096 MB
        Form Factor: DIMM
        Set: None
        Locator: DIMM1
        Bank Locator: BANK1
        Type: DDR
        Type Detail: Synchronous
        Speed: 1333 MHz
        Manufacturer: Manufacturer1
        Serial Number: SerNum1
        Asset Tag: AssetTagNum1
        Part Number: PartNum1
        Rank: Unknown

Handle 0x0036, DMI type 17, 28 bytes
Memory Device
        Array Handle: 0x0030
        Error Information Handle: Not Provided
        Total Width: 64 bits
        Data Width: 64 bits
        Size: 2048 MB
        Form Factor: DIMM
        Set: None
        Locator: DIMM2
        Bank Locator: BANK2
        Type: DDR
        Type Detail: Synchronous
        Speed: 1333 MHz
        Manufacturer: Manufacturer2
        Serial Number: SerNum2
        Asset Tag: AssetTagNum2
        Part Number: PartNum2
        Rank: Unknown

Handle 0x0038, DMI type 17, 28 bytes
Memory Device
        Array Handle: 0x0030
        Error Information Handle: Not Provided
        Total Width: 64 bits
        Data Width: 64 bits
        Size: 4096 MB
        Form Factor: DIMM
        Set: None
        Locator: DIMM3
        Bank Locator: BANK3
        Type: DDR
        Type Detail: Synchronous
        Speed: 1333 MHz
        Manufacturer: Manufacturer3
        Serial Number: SerNum3
        Asset Tag: AssetTagNum3
        Part Number: PartNum3
        Rank: Unknown

$ free
             total       used       free     shared    buffers     cached
Mem:       6102336    5605508     496828      31384     769868    3664868
-/+ buffers/cache:    1170772    4931564
Swap:      6282236     103584    6178652

설치 했는데도 free나만 보이는 것 같네요 . 왜?6G12

고쳐 쓰다

상단의 일부 출력 dmesg:

[    0.000000] reg 0, base: 0GB, range: 4GB, type WB
[    0.000000] reg 1, base: 4GB, range: 2GB, type WB
[    0.000000] reg 2, base: 6GB, range: 512MB, type WB
[    0.000000] reg 3, base: 3584MB, range: 512MB, type UC
[    0.000000] total RAM covered: 6144M

업데이트 2

~$ df -h
Filesystem      Size  Used Avail Use% Mounted on
udev            2.9G   12K  2.9G   1% /dev
tmpfs           596M   21M  576M   4% /run
/dev/sda1       288G   29G  245G  11% /
none            4.0K     0  4.0K   0% /sys/fs/cgroup
none            5.0M  4.0K  5.0M   1% /run/lock
none            3.0G  148K  3.0G   1% /run/shm
none            100M   40K  100M   1% /run/user

업데이트 3

마더보드는ASUS P7P55-M, 메모리 슬롯의 물리적인 모양은 다음과 같습니다.

여기에 이미지 설명을 입력하세요.

설명서에 있는 사진은 다음과 같습니다

여기에 이미지 설명을 입력하세요.

2G DIMM 2개와 4G DIMM 2개를 가지고 있는데 사이즈별로 색상별로 꽂아봤습니다.

관련 정보