installed 12GB, detected 11GB. Why?

I have a 4 memory slot mobo (asus M4A77TD)
I have the 4 slot populated with 2+2+4+4GB


fernando@andromeda:~> free -h
             total       used       free     shared    buffers     cached
Mem:           11G       3,4G       8,3G        54M       226M       1,4G
-/+ buffers/cache:       1,8G         9G
Swap:          16G         0B        16G
fernando@andromeda:~> 



why?

Apparently ‘free -h’ does not round the results but just truncates them; try ‘free -m’ as a comparison.
For a better gauge try ‘top’ and look at the third and fourth lines for memory statistics.

Along with that, I think the labels on the units are wrong. For example,
my laptop has 16750329856 bytes of RAM, which is 16 or so gigabytes, but
it is only 15.9 gibibytes, and that is what I think free actually shows,
just like by default it shows kibibytes. See wikipedia for explanations
of the difference, and otherwise you can calculate the same thing at the
command line:


#force the math library
echo $(free | awk '/^Mem:/ {print $2}')/1024/1024 | bc -l

#and if you disable the long output:
echo $(free | awk '/^Mem:/ {print $2}')/1024/1024 | bc


Good luck.

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show your appreciation and click on the star below…

It has always been thus.

I’ve been using linux since 1995. And “free” has always listed a smaller amount of memory than the BIOS shows. It is probably not listing the memory that is in use by the kernel.

Out of curiosity, have you tried using dmidecode? I have not personally used it, but the description is as follows:

Dmidecode reports information about your system’s hardware as described in your system BIOS according to the SMBIOS/DMI standard. This information typically includes system manufacturer, model name, serial number, BIOS version, asset tag as well as a lot of other details of varying level of interest and reliability depending on the manufacturer. This will often include usage status for the CPU sockets, expansion slots (e.g. AGP, PCI, ISA) and memory module slots, and the list of I/O ports (e.g. serial, parallel, USB). Beware that DMI data have proven to be too unreliable to be blindly trusted. Dmidecode does not scan your hardware, it only reports what the BIOS told it to.

You can install it for openSUSE here:
http://software.opensuse.org/package/dmidecode

After the installation, you should be able to run the following line:

sudo dmidecode -t 17 

The output should be something along the lines of:

# dmidecode 2.9
SMBIOS 2.4 present.

Handle 0x0023, DMI type 17, 27 bytes
Memory Device
        Array Handle: 0x0022
        Error Information Handle: Not Provided
        Total Width: 72 bits
        Data Width: 64 bits
        Size: **1024 MB
        **Form Factor:** DIMM**
        Set: None
        Locator: J8J1
        Bank Locator: **CHAN A DIMM 1**
        Type: **DDR2**
        Type Detail: **Synchronous**
        Speed: **533 MHz (1.9 ns)**
        Manufacturer: 0x7F98000000000000
        Serial Number: 0x813625B6
        Asset Tag: Unknown
        Part Number: 0x393930353332312D3030312E4130334C4600

Handle 0x0025, DMI type 17, 27 bytes
Memory Device
        Array Handle: 0x0022
        Error Information Handle: Not Provided
        Total Width: Unknown
        Data Width: Unknown
        Size: **No Module Installed**
        Form Factor: DIMM
        Set: None
        Locator: J8J2
        Bank Locator: CHAN A DIMM 2
        Type: DDR2
        Type Detail: None
        Speed: Unknown
        Manufacturer: NO DIMM
        Serial Number: NO DIMM
        Asset Tag: NO DIMM
        Part Number: NO DIMM

Handle 0x0026, DMI type 17, 27 bytes
Memory Device
        Array Handle: 0x0022
        Error Information Handle: Not Provided
        Total Width: 72 bits
        Data Width: 64 bits
        Size: **1024 MB**
        Form Factor: **DIMM**
        Set: None
        Locator: J9J1
        Bank Locator: **CHAN B DIMM 1**
        Type: **DDR2**
        Type Detail: **Synchronous**
        Speed: **533 MHz (1.9 ns)**
        Manufacturer: 0x7F98000000000000
        Serial Number: 0x82363EB6
        Asset Tag: Unknown
        Part Number: 0x393930353332312D3030312E4130334C4600

Handle 0x0028, DMI type 17, 27 bytes
Memory Device
        Array Handle: 0x0022
        Error Information Handle: Not Provided
        Total Width: Unknown
        Data Width: Unknown
        Size: **No Module Installed**
        Form Factor: DIMM
        Set: None
        Locator: J9J2
        Bank Locator: CHAN B DIMM 2
        Type: DDR2
        Type Detail: None
        Speed: Unknown
        Manufacturer: NO DIMM
        Serial Number: NO DIMM
        Asset Tag: NO DIMM
        Part Number: NO DIMM

Regards,
tstor

it seems so


fernando@andromeda:~> free -h
             total       used       free     shared    buffers     cached
Mem:           11G       6,9G       4,9G       2,5G       273M       4,7G
-/+ buffers/cache:       2,0G       9,8G
Swap:          16G         0B        16G
fernando@andromeda:~> free 
             total       used       free     shared    buffers     cached
Mem:      12326656    7240516    5086140    2649164     280068    4889584
-/+ buffers/cache:    2070864   10255792
Swap:     17028060          0   17028060
fernando@andromeda:~> free  -m
             total       used       free     shared    buffers     cached
Mem:         12037       7460       4577       2588        274       4821
-/+ buffers/cache:       2364       9672
Swap:        16628          0      16628
fernando@andromeda:~>


12326656 K is 11.75561523 G it seems free rounds memory amount in used,free, shared, buffers and cached, but it truncates it in total.

This is funny … I’ve run out of memory!! :slight_smile:


fernando@andromeda:~> free  --tera
             total       used       free     shared    buffers     cached
Mem:             0          0          0          0          0          0
-/+ buffers/cache:          0          0
Swap:            0          0          0
fernando@andromeda:~> 


I didn’t know ot but I had it already installed. I liked it.


andromeda:/home/fernando # dmidecode -t 17
# dmidecode 2.12
SMBIOS 2.5 present.

Handle 0x0034, DMI type 17, 27 bytes
Memory Device
        Array Handle: 0x0032
        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: Other
        Type Detail: Synchronous
        Speed: 1333 MHz
        Manufacturer: Manufacturer0
        Serial Number: SerNum0
        Asset Tag: AssetTagNum0
        Part Number: PartNum0

Handle 0x0036, DMI type 17, 27 bytes
Memory Device
        Array Handle: 0x0032
        Error Information Handle: Not Provided
        Total Width: 64 bits
        Data Width: 64 bits
        Size: 2048 MB
        Form Factor: DIMM
        Set: None
        Locator: DIMM1
        Bank Locator: BANK1
        Type: Other
        Type Detail: Synchronous
        Speed: 1333 MHz
        Manufacturer: Manufacturer1
        Serial Number: SerNum1
        Asset Tag: AssetTagNum1
        Part Number: PartNum1

Handle 0x0038, DMI type 17, 27 bytes
Memory Device
        Array Handle: 0x0032
        Error Information Handle: Not Provided
        Total Width: 64 bits
        Data Width: 64 bits
        Size: 4096 MB
        Form Factor: DIMM
        Set: None
        Locator: DIMM2
        Bank Locator: BANK2
        Type: Other
        Type Detail: Synchronous
        Speed: 1333 MHz
        Manufacturer: Manufacturer2
        Serial Number: SerNum2
        Asset Tag: AssetTagNum2
        Part Number: PartNum2

Handle 0x003A, DMI type 17, 27 bytes
Memory Device
        Array Handle: 0x0032
        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: Other
        Type Detail: Synchronous
        Speed: 1333 MHz
        Manufacturer: Manufacturer3
        Serial Number: SerNum3
        Asset Tag: AssetTagNum3
        Part Number: PartNum3

andromeda:/home/fernando # 


regards

Get used to it. This has been happening to me for the past couple of decades. Has to do with aging.:stuck_out_tongue: