Ubuntu 18.04 не показывает максимально полезную память

Спецификации -

CPU - Ryzen 5 2400G
Motherboard - MSI B450 gaming plus
RAM - Corsair Vengeance 8GB x 2
I am Using two displays - HDMI && DVI

Я установил Ubuntu 18.04, и он показывает только 13,7 ГБ оперативной памяти из 16 ГБ

И когда я использую только одну флешку, она показывает 5,8 ГБ из 8 ГБ

Я был на Windows, и там ОЗУ было 14+ ГБ

sudo dmidecode -t memory

Выход

# dmidecode 3.1
Getting SMBIOS data from sysfs.
SMBIOS 2.8 present.

Handle 0x000F, DMI type 16, 23 bytes
Physical Memory Array
    Location: System Board Or Motherboard
    Use: System Memory
    Error Correction Type: None
    Maximum Capacity: 256 GB
    Error Information Handle: 0x000E
    Number Of Devices: 4

Handle 0x0016, DMI type 17, 40 bytes
Memory Device
    Array Handle: 0x000F
    Error Information Handle: 0x0015
    Total Width: Unknown
    Data Width: Unknown
    Size: No Module Installed
    Form Factor: Unknown
    Set: None
    Locator: DIMM 0
    Bank Locator: P0 CHANNEL A
    Type: Unknown
    Type Detail: Unknown
    Speed: 2133 MT/s
    Manufacturer: Unknown
    Serial Number: Unknown
    Asset Tag: Not Specified
    Part Number: Unknown
    Rank: Unknown
    Configured Clock Speed: Unknown
    Minimum Voltage: Unknown
    Maximum Voltage: Unknown
    Configured Voltage: Unknown

Handle 0x0018, DMI type 17, 40 bytes
Memory Device
    Array Handle: 0x000F
    Error Information Handle: 0x0017
    Total Width: 64 bits
    Data Width: 64 bits
    Size: 8192 MB
    Form Factor: DIMM
    Set: None
    Locator: DIMM 1
    Bank Locator: P0 CHANNEL A
    Type: DDR4
    Type Detail: Synchronous Unbuffered (Unregistered)
    Speed: 2133 MT/s
    Manufacturer: Unknown
    Serial Number: 00000000
    Asset Tag: Not Specified
    Part Number: CMK8GX4M1D3000C16   
    Rank: 1
    Configured Clock Speed: 1067 MT/s
    Minimum Voltage: 1.2 V
    Maximum Voltage: 1.2 V
    Configured Voltage: 1.2 V

Handle 0x001B, DMI type 17, 40 bytes
Memory Device
    Array Handle: 0x000F
    Error Information Handle: 0x001A
    Total Width: Unknown
    Data Width: Unknown
    Size: No Module Installed
    Form Factor: Unknown
    Set: None
    Locator: DIMM 0
    Bank Locator: P0 CHANNEL B
    Type: Unknown
    Type Detail: Unknown
    Speed: 2133 MT/s
    Manufacturer: Unknown
    Serial Number: Unknown
    Asset Tag: Not Specified
    Part Number: Unknown
    Rank: Unknown
    Configured Clock Speed: Unknown
    Minimum Voltage: Unknown
    Maximum Voltage: Unknown
    Configured Voltage: Unknown

Handle 0x001D, DMI type 17, 40 bytes
Memory Device
    Array Handle: 0x000F
    Error Information Handle: 0x001C
    Total Width: 64 bits
    Data Width: 64 bits
    Size: 8192 MB
    Form Factor: DIMM
    Set: None
    Locator: DIMM 1
    Bank Locator: P0 CHANNEL B
    Type: DDR4
    Type Detail: Synchronous Unbuffered (Unregistered)
    Speed: 2133 MT/s
    Manufacturer: Unknown
    Serial Number: 00000000
    Asset Tag: Not Specified
    Part Number: CMK8GX4M1D3000C16   
    Rank: 1
    Configured Clock Speed: 1067 MT/s
    Minimum Voltage: 1.2 V
    Maximum Voltage: 1.2 V
    Configured Voltage: 1.2 V