Number of RAM slots

Question

I am trying to figure out how many free RAM slots are available in my laptop so that I can upgrade them. I have inbuilt two 4gb (8gb) RAM, however I would like to upgrade it to 16gb. I tried using sudo dmidecode -t memory which gives me this

# dmidecode 3.0
Getting SMBIOS data from sysfs.
SMBIOS 3.0 present.

Handle 0x000D, 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: No Error
Number Of Devices: 2

Handle 0x000E, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x000D
Error Information Handle: No Error
Total Width: 64 bits
Data Width: 64 bits
Size: 4096 MB
Form Factor: SODIMM
Set: None
Locator: ChannelA-DIMM0
Bank Locator: BANK 0
Type: DDR4
Type Detail: Synchronous
Speed: 2133 MHz
Manufacturer: Micron
Serial Number: 1570FAFC
Asset Tag: 9876543210
Part Number: 4ATF51264HZ-2G3B1   
Rank: 1
Configured Clock Speed: 2133 MHz
Minimum Voltage: 1.5 V
Maximum Voltage: 1.5 V
Configured Voltage: 1.2 V

Handle 0x000F, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x000D
Error Information Handle: No Error
Total Width: Unknown
Data Width: Unknown
Size: No Module Installed
Form Factor: Unknown
Set: None
Locator: ChannelA-DIMM1
Bank Locator: BANK 1
Type: Unknown
Type Detail: None
Speed: Unknown
Manufacturer: Not Specified
Serial Number: Not Specified
Asset Tag: Not Specified
Part Number: Not Specified
Rank: Unknown
Configured Clock Speed: Unknown
Minimum Voltage: Unknown
Maximum Voltage: Unknown
Configured Voltage: Unknown

Handle 0x0010, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x000D
Error Information Handle: No Error
Total Width: 64 bits
Data Width: 64 bits
Size: 4096 MB
Form Factor: SODIMM
Set: None
Locator: ChannelB-DIMM0
Bank Locator: BANK 2
Type: DDR4
Type Detail: Synchronous
Speed: 2133 MHz
Manufacturer: Micron
Serial Number: 1570FB42
Asset Tag: 9876543210
Part Number: 4ATF51264HZ-2G3B1   
Rank: 1
Configured Clock Speed: 2133 MHz
Minimum Voltage: 1.5 V
Maximum Voltage: 1.5 V
Configured Voltage: 1.2 V

Handle 0x0011, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x000D
Error Information Handle: No Error
Total Width: Unknown
Data Width: Unknown
Size: No Module Installed
Form Factor: Unknown
Set: None
Locator: ChannelB-DIMM1
Bank Locator: BANK 3
Type: Unknown
Type Detail: None
Speed: Unknown
Manufacturer: Not Specified
Serial Number: Not Specified
Asset Tag: Not Specified
Part Number: Not Specified
Rank: Unknown
Configured Clock Speed: Unknown
Minimum Voltage: Unknown
Maximum Voltage: Unknown
Configured Voltage: Unknown

I don't understand what are these BANK 1 and BANK 3 for? I would like to understand the dmidecode. Do I have 2 ram slots or 4? Does this bank indicate some other ports like m.2 sata? I have Acer E5-575g laptop. Any help would be appreciated, thanks.

Answer 1

The sudo dmidecode -t memory command that you ran in your question is too verbose. The command sudo dmidecode --type 17 gives more concise results. The number of memory devices in the results of sudo dmidecode --type 17 is equal to the number of memory slots, so the command to print the number of RAM slots is:

sudo dmidecode --type 17 | grep 'Memory Device' --count  

The results of this command will be one integer number equal to the number of RAM slots.

The command to show the size of each of the installed RAM sticks is:

 sudo dmidecode --type 17 | grep -i size  

This is a very informative command because it shows the number of empty RAM slots, the number of RAM slots that have RAM sticks installed and the size of each installed RAM stick.

This example output shows that the computer has 4 RAM slots (2 empty slots & 2 full slots), and two 4GB RAM sticks (8GB RAM).

$ sudo dmidecode --type 17 | grep 'Memory Device' --count
4
$ sudo dmidecode --type 17 | grep -i size
    Size: No Module Installed
    Size: No Module Installed
    Size: 4096 MB
    Size: 4096 MB

For more verbose and well formatted output run the following command:

sudo inxi -m