无法从 Linux 获取双通道内存状态——为什么？

Question

我有一个插槽 A3+ 主板（技嘉 ATX GA990ZA-UD3-R5），带有 AMD FX-8320E CPU 和两个 8Gb 记忆棒（相同，作为套件一起购买）。我按照手册上的说明安装了内存以使用双通道内存，但据我所知，我无法查询系统有关内存的信息（使用Linux）：

lshw 什么都不说：

$ sudo lshw -C memory
  *-memory                
       description: System memory
       physical id: 0
       size: 15GiB

并dmidecode没有说交错：

$ sudo dmidecode --type memory
# dmidecode 3.0
Getting SMBIOS data from sysfs.
SMBIOS 2.7 present.

Handle 0x0008, DMI type 5, 24 bytes
Memory Controller Information
    Error Detecting Method: 64-bit ECC
    Error Correcting Capabilities:
        None
    Supported Interleave: One-way Interleave
    Current Interleave: One-way Interleave
    Maximum Memory Module Size: 2048 MB
    Maximum Total Memory Size: 8192 MB
    Supported Speeds:
        70 ns
        60 ns
    Supported Memory Types:
        DIMM
        SDRAM
    Memory Module Voltage: 3.3 V
    Associated Memory Slots: 4
        0x0009
        0x000A
        0x000B
        0x000C
    Enabled Error Correcting Capabilities:
        None

Handle 0x0009, DMI type 6, 12 bytes
Memory Module Information
    Socket Designation: DIMM0
    Bank Connections: 0 1
    Current Speed: 60 ns
    Type: DIMM SDRAM
    Installed Size: 536870912 MB (Single-bank Connection)
    Enabled Size: 536870912 MB (Single-bank Connection)
    Error Status: OK

Handle 0x000A, DMI type 6, 12 bytes
Memory Module Information
    Socket Designation: DIMM1
    Bank Connections: 2 3
    Current Speed: 60 ns
    Type: DIMM SDRAM
    Installed Size: 536870912 MB (Single-bank Connection)
    Enabled Size: 536870912 MB (Single-bank Connection)
    Error Status: OK

Handle 0x000B, DMI type 6, 12 bytes
Memory Module Information
    Socket Designation: DIMM2
    Bank Connections: 4 5
    Current Speed: 60 ns
    Type: DIMM SDRAM
    Installed Size: 536870912 MB (Single-bank Connection)
    Enabled Size: 536870912 MB (Single-bank Connection)
    Error Status: OK

Handle 0x000C, DMI type 6, 12 bytes
Memory Module Information
    Socket Designation: DIMM3
    Bank Connections: 6 7
    Current Speed: 60 ns
    Type: DIMM SDRAM
    Installed Size: 536870912 MB (Single-bank Connection)
    Enabled Size: 536870912 MB (Single-bank Connection)
    Error Status: OK

Handle 0x002C, DMI type 16, 23 bytes
Physical Memory Array
    Location: System Board Or Motherboard
    Use: System Memory
    Error Correction Type: None
    Maximum Capacity: 32 GB
    Error Information Handle: Not Provided
    Number Of Devices: 4

Handle 0x002E, DMI type 17, 34 bytes
Memory Device
    Array Handle: 0x002C
    Error Information Handle: Not Provided
    Total Width: Unknown
    Data Width: 64 bits
    Size: No Module Installed
    Form Factor: DIMM
    Set: None
    Locator: Node0_Dimm0
    Bank Locator: Node0_Bank0
    Type: Unknown
    Type Detail: Synchronous
    Speed: Unknown
    Manufacturer: Dimm0_Manufacturer
    Serial Number: Dimm0_SerNum
    Asset Tag: Dimm0_AssetTag
    Part Number: Dimm0_PartNum
    Rank: Unknown
    Configured Clock Speed: Unknown

Handle 0x0030, DMI type 17, 34 bytes
Memory Device
    Array Handle: 0x002C
    Error Information Handle: Not Provided
    Total Width: 64 bits
    Data Width: 64 bits
    Size: 8192 MB
    Form Factor: DIMM
    Set: None
    Locator: Node0_Dimm1
    Bank Locator: Node0_Bank0
    Type: DDR3
    Type Detail: Synchronous Unbuffered (Unregistered)
    Speed: 933 MHz
    Manufacturer: Kingston          
    Serial Number: 4D384FFC    
    Asset Tag: Dimm1_AssetTag
    Part Number: KHX1866C10D3/
    Rank: 2
    Configured Clock Speed: 933 MHz

Handle 0x0032, DMI type 17, 34 bytes
Memory Device
    Array Handle: 0x002C
    Error Information Handle: Not Provided
    Total Width: Unknown
    Data Width: 64 bits
    Size: No Module Installed
    Form Factor: DIMM
    Set: None
    Locator: Node0_Dimm2
    Bank Locator: Node0_Bank0
    Type: Unknown
    Type Detail: Synchronous
    Speed: Unknown
    Manufacturer: Dimm2_Manufacturer
    Serial Number: Dimm2_SerNum
    Asset Tag: Dimm2_AssetTag
    Part Number: Dimm2_PartNum
    Rank: Unknown
    Configured Clock Speed: Unknown

Handle 0x0034, DMI type 17, 34 bytes
Memory Device
    Array Handle: 0x002C
    Error Information Handle: Not Provided
    Total Width: 64 bits
    Data Width: 64 bits
    Size: 8192 MB
    Form Factor: DIMM
    Set: None
    Locator: Node0_Dimm3
    Bank Locator: Node0_Bank0
    Type: DDR3
    Type Detail: Synchronous Unbuffered (Unregistered)
    Speed: 933 MHz
    Manufacturer: Kingston          
    Serial Number: 6B39AD31    
    Asset Tag: Dimm3_AssetTag
    Part Number: KHX1866C10D3/
    Rank: 2
    Configured Clock Speed: 933 MHz

（记忆棒的速度为 1866MHz，我不知道为什么它在 .BIOS 中显示为 933MHz。BIOSdmidecode报告它为 1866MHz。）

此主板不显示 POST 消息。它显示一个闪屏，然后提供进入设置。之后，在引导加载程序介入之前，它什么也不打印。我搜索了所有设置选项，也看不到与双通道激活或未激活相关的任何内容。

我不确定这是否相关，但我在 BIOS 中启用了IOMMU ，并iommu=soft在启动时将该选项传递给 Linux 内核。

我怎么能确定自己是否拥有双通道的工作，而且，为什么lshw并dmidecode没有告知双通道？

Answer 1

尝试这个：

dmidecode -t 17 |grep 通道

对于双通道，您应该将通道 A/B 视为：

Locator: ChannelA-DIMM0
Locator: ChannelA-DIMM1
Locator: ChannelB-DIMM0
Locator: ChannelB-DIMM1