我使用的是华硕笔记本电脑，内置 4GB RAM 内存。
我的操作系统是 Ubuntu 17.10（64 位）。
在空闲插槽中插入额外的 4GB 内存后，大多数实用程序仍将内存量识别为 4GB。
但是，如果我运行，sudo lshw -short -C memory则会列出新的内存卡。
你能帮我诊断一下这个问题吗？
以下是一些特定于内存的实用程序的输出：
free -h
total used free shared buff/cache available
Mem: 3,7G 1,1G 1,4G 251M 1,2G 2,2G
Swap: 8,0G 0B 8,0G
sudo lshw -short -C memory
H/W path Device Class Description
============================================================
/0/0 memory 64KiB BIOS
/0/8 memory 512KiB L2 cache
/0/9 memory 128KiB L1 cache
/0/a memory 3MiB L3 cache
/0/b memory 4GiB System Memory
/0/b/0 memory 4GiB SODIMM DDR3 Synchronous 1333 MHz (0,8 ns)
/0/b/1 memory DIMM [empty]
/0/b/2 memory DIMM [empty]
/0/b/3 memory DIMM [empty]
sudo lshw -C memory
[sudo] password for tomek:
*-firmware
description: BIOS
vendor: American Megatrends Inc.
physical id: 0
version: X55VD.409
date: 01/08/2013
size: 64KiB
capacity: 6080KiB
capabilities: pci upgrade shadowing cdboot bootselect
socketedrom edd int13floppy1200 int13floppy720 int13floppy2880
int5printscreen int9keyboard int14serial int17printer acpi usb
smartbattery biosbootspecification uefi
*-cache:0
description: L2 cache
physical id: 8
slot: CPU Internal L2
size: 512KiB
capacity: 512KiB
capabilities: internal write-through unified
configuration: level=2
*-cache:1
description: L1 cache
physical id: 9
slot: CPU Internal L1
size: 128KiB
capacity: 128KiB
capabilities: internal write-through data
configuration: level=1
*-cache:2
description: L3 cache
physical id: a
slot: CPU Internal L3
size: 3MiB
capacity: 3MiB
capabilities: internal write-back unified
configuration: level=3
*-memory
description: System Memory
physical id: b
slot: System board or motherboard
size: 4GiB
*-bank:0
description: SODIMM DDR3 Synchronous 1333 MHz (0,8 ns)
product: EBJ40UG8BBU0-GN-F
vendor: Elpida
physical id: 0
serial: 00000000
slot: ChannelA-DIMM0
size: 4GiB
width: 64 bits
clock: 1333MHz (0.8ns)
*-bank:1
description: DIMM [empty]
product: [Empty]
vendor: [Empty]
physical id: 1
serial: [Empty]
slot: ChannelA-DIMM1
*-bank:2
description: DIMM [empty]
product: [Empty]
vendor: [Empty]
physical id: 2
serial: [Empty]
slot: ChannelB-DIMM0
*-bank:3
description: DIMM [empty]
product: [Empty]
vendor: [Empty]
physical id: 3
serial: [Empty]
slot: ChannelB-DIMM1
sudo dmidecode --type memory
# dmidecode 3.1
Getting SMBIOS data from sysfs.
SMBIOS 2.7 present.
Handle 0x000B, 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 0x000D, DMI type 17, 34 bytes
Memory Device
Array Handle: 0x000B
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 4096 MB
Form Factor: SODIMM
Set: None
Locator: ChannelA-DIMM0
Bank Locator: BANK 0
Type: DDR3
Type Detail: Synchronous
Speed: 1333 MT/s
Manufacturer: Elpida
Serial Number: 00000000
Asset Tag: 9876543210
Part Number: EBJ40UG8BBU0-GN-F
Rank: 1
Configured Clock Speed: 1333 MT/s
Handle 0x000F, DMI type 17, 34 bytes
Memory Device
Array Handle: 0x000B
Error Information Handle: Not Provided
Total Width: Unknown
Data Width: Unknown
Size: No Module Installed
Form Factor: DIMM
Set: None
Locator: ChannelA-DIMM1
Bank Locator: BANK 1
Type: Unknown
Type Detail: None
Speed: Unknown
Manufacturer: [Empty]
Serial Number: [Empty]
Asset Tag: 9876543210
Part Number: [Empty]
Rank: Unknown
Configured Clock Speed: Unknown
Handle 0x0010, DMI type 17, 34 bytes
Memory Device
Array Handle: 0x000B
Error Information Handle: Not Provided
Total Width: Unknown
Data Width: Unknown
Size: No Module Installed
Form Factor: DIMM
Set: None
Locator: ChannelB-DIMM0
Bank Locator: BANK 2
Type: Unknown
Type Detail: None
Speed: Unknown
Manufacturer: [Empty]
Serial Number: [Empty]
Asset Tag: 9876543210
Part Number: [Empty]
Rank: Unknown
Configured Clock Speed: Unknown
Handle 0x0011, DMI type 17, 34 bytes
Memory Device
Array Handle: 0x000B
Error Information Handle: Not Provided
Total Width: Unknown
Data Width: Unknown
Size: No Module Installed
Form Factor: DIMM
Set: None
Locator: ChannelB-DIMM1
Bank Locator: BANK 3
Type: Unknown
Type Detail: None
Speed: Unknown
Manufacturer: [Empty]
Serial Number: [Empty]
Asset Tag: 9876543210
Part Number: [Empty]
Rank: Unknown
Configured Clock Speed: Unknown