Linux Basics: How to find the maximum memory _linux your system supports

In most cases, you can find the maximum memory that your system holds, either from the BIOS, the product catalog, or simply manually. Here, we introduce a simple and useful technique--use Dmidecode to find the maximum memory that the system supports, so you don't have to open the chassis or reference the BIOS or the product catalog.

What is Dmidecode?

As you may know, Dmidecode is a tool that converts the contents of the computer's DMI (or name smbios) table to a readable format. This table contains a description of the system hardware components and other useful information, such as serial numbers and iOS versions. Using Dmidecode you can get this information without having to detect real hardware.

Find the maximum memory supported by your system

Make sure you have installed the Dmidecode in the system, I think your operating system should have been installed automatically, but not very sure.

Installing in a Deb based system

sudo apt-get install Dmidecode

Installing in an RPM based system

sudo yum install Dmidecode

Installing in Suse/opensuse

sudo zypper in Dmidecode

OK, we've installed the Dmidecode, and next let's figure out the maximum memory supported. Enter the following command:

sudo dmidecode-t 16

Output sample

# Dmidecode 2.12
SMBIOS 2.6 present.
 
Handle 0x0014, DMI type, bytes
physical Memory Array
 location:system Board Or motherboard
 use:system M Emory
 Error correction type:none
 Maximum capacity:16 GB
 Error information Handle:not provided number
 O F Devices:2

As you can see, my system supports maximum memory to 16G and has two memory slots, is it easy?

Next, let's find out more about the memory that is now installed.

sudo dmidecode-t 17

Output sample

 Dmidecode 2.12 SMBIOS 2.6. Handle 0x0017, DMI type, bytes Memory Device Array handle:0x0014 Error information handle:0x0000 Total width:u Nknown Data width:unknown size:no Module installed Form factor:dimm set:none locator:dimm_b Bank Locator:bank  2 Type:unknown Type detail:none speed:unknown manufacturer:not Specified serial number:not Specified Asset Tag: Not Specified part number:not Specified rank:unknown Handle 0x0015, DMI type, bytes Memory Array Device le:0x0014 Error information handle:0x0000 total width:64 bits Data width:64 bits size:4096 MB Form Factor:sodim M set:none locator:dimm_a Bank locator:bank 0 type:ddr3 Type detail:synchronous MHz speed:1067: 014F serial number:00092af2 Asset tag:54114000 part number:jm1066ksn-4g Rank:unknown 

Like the output above, I have a memory bar in slot 1. The memory size is 4G, the type is DDR3, and the speed is 1067 MHz.

In the same way, we can get complete memory information through the command below.

sudo dmidecode-t memory
sudo dmidecode-t memory | Less
sudo dmidecode-t memory | more

Output sample

# Dmidecode 2.12 SMBIOS 2.6 present. Handle 0x0014, DMI type, bytes physical Memory Array location:system Board Or motherboard Use:system ERR or correction type:none Maximum capacity:16 GB Error Information Handle:not provided number of Devices:2 Handle 0
 x0017, DMI type, bytes Memory Device Array handle:0x0014 Error information handle:0x0000 Total Width:unknown  Data width:unknown size:no Module installed Form factor:dimm set:none locator:dimm_b Bank locator:bank 2 Type: Unknown Type detail:none speed:unknown manufacturer:not Specified serial number:not Specified Asset tag:not Spe Cified part number:not Specified rank:unknown Handle 0x0015, DMI type, bytes Memory Array Device The Error information handle:0x0000 total width:64 bits Data width:64 bits size:4096 MB Form factor:sodimm Set: None locator:dimm_a Bank locator:bank 0 type:ddr3 Type detail:synchronous speed:1067 MHz manufacturer:014f serial number:00092af2 Asset tag:54114000 part number:jm1066ksn-4g Rank:unknown
 

If you are curious to know the details of the entire system, such as the motherboard, memory, BIOS, and so on, you can enter the following command to obtain it.

sudo dmidecode

Output sample

# Dmidecode 2.12 SMBIOS 2.6 present.
Structures occupying 2173 bytes.
 
Table at 0x000eb840. Handle 0xda00, DMI type 218, 251 bytes oem-specific type Header and Data:da FB DA B2 0D 5F 0F 7D 00 00 00  (7E) (a) A/2D (2E) (a) (a) "A/M", A/DD 01 03 80 00 00 81 01 07 80 00 00 82 01 07 80 01 00 83 01 08 80 00 00 84 01 08 80 01 00 85 01 06 80 00 00 86-01  The other 9C, all of the "9B", all of the other 8A), for the most of all, for the same. All the 01 06 00 01 00 94 01 07 00, at the same (7B), at the same, at the same.  For the 7D 2D, 01 00 96, at the 2E of the 0A for the most-so-so-to-be-so- 0B 2F 0C (0D) 0D (00) FF 0D (00) (+) for the most-so-for- Handle 0xda01, DMI type 218, bytes OEM-specific Type Header and Data:da 3B DA B2 0D 5F 0F (05) 0D (0D) 0D 00 0 0 4 B 0E 4 a 0E Handle 0x0004, the DMI type, and the same as the same as the same as the other. 4 type:central bytes Processor information Socket designation:cpu 1 Processor family:core i3 manufacturer:inte L ID:A7-FF FB AB be signature:type 0, Family 6, Model, stepping 7 flags:fpu (floating-point)
  -chip) VME (Virtual mode extension) DE (Debugging Extension) PSE (Page size extension) TSC (time stamp counter) MSR (Model specific registers) PAE (Physical Address Extension) MCE (Machine check exception) CX8 (CMPXCHG8 instruct Ion supported) APIC (on-chip APIC Hardware supported) SEP (Fast system call) MTRR (Memory type range registers) PG E (page global Enable) MCA (Machine Check Architecture) Cmov (Conditional move instruction supported) PAT (page attr Ibute table) PSE-36 (36-bit page size extension) CLFSH (Clflush instruction supported) DS (Debug Store) ACPI (ACPI supported) MMX (MMX t  Echnology supported) FXSR (Fxsave and fxstor instructions supported) SSE (streaming SIMD extensions) SSE2 (streaming SIMD Extensions 2) SS (Self-snoop) HTT (multi-threading) TM (Thermal Monitor supported) PBE (Pending break enable d) Version:intel (R) Core (TM) i3-2350m CPU @ 2.30GHz voltage:1.1 V External clock:100 MHz Max speed:2300 MHz Cur Rent speed:2300 MHz status:populated, Enabled upgrade:other L1 cache handle:0x0005 L2 cache handle:0x0006 L3 Cac
 He handle:0x0007 serial number:to is filled by O.E.M.
 Asset tag:to is filled by O.E.M.
 Part number:to is filled by O.E.M. Core Count:2 core Enabled:1 Thread count:2 characteristics:64-bit capable Handle 0x0005, DMI type 7, bytes C Ache information Socket Designation:l1-cache configuration:enabled, not socketed, Level 1 operational mode:write Bac K Location:intErnal installed size:64 KB Maximum size:64 KB supported SRAM Types:other installed SRAM Type:other Speed:unkno WN Error correction type:none System type:unified associativity:8-way set-associative Handle 0x0006, DMI Type 7, 1 9 bytes Cache Information Socket designation:l2-cache configuration:enabled, not socketed, Level 2 operational Mode: Varies with Memory address location:internal installed size:512 KB Maximum size:512 KB supported SRAM types:othe R installed SRAM type:other speed:unknown Error correction type:none System type:unified associativity:8-way Set -associative Handle 0x0007, DMI type 7, bytes Cache information Socket designation:l3-cache configuration:enabled , not socketed, Level 3 operational mode:varies with Memory address location:internal installed size:3072 KB Maximu M size:3072 KB supported SRAM Types:other installed SRAM Type:other speed:unknown Error correction Type:none S Ystem type:unified AssOciativity:other 0x0008 Handle, DMI type 8, 9 bytes Port Connector information Internal Reference DESIGNATOR:J1A1 in 
 
ternal Connector type:none External Reference designator:ps2mouse External Connector type:ps/2 Port Type:mouse Port Handle 0x0009, DMI type 8, 9 bytes Port Connector information Internal Reference designator:j1a1 Internal Connector Type:none External Reference designator:keyboard External Connector type:ps/2 Port Type:keyboard Port Handle 0x00 0A, DMI type 8, 9 bytes Port Connector information Internal Reference designator:j2a2b Internal Connector type:none E xternal Reference designator:video External Connector type:db-15 female port type:video Port Handle 0x000b, DMI Typ E 8, 9 bytes Port Connector information Internal Reference designator:j3a1 Internal Connector type:none External Rence designator:usb1 External Connector type:access Bus (USB) Port type:usb Handle, DMI Type 8, 9 0x000c bytes
T Connector information Internal Reference designator:j3a1 Internal Connector type:none External Reference designator:usb2 External Connect or Type:access bus (USB) Port type:usb Handle 0x000d, DMI Type 8, 9 bytes Port Connector information Internal nce designator:j3a1 Internal Connector type:none External Reference designator:usb3 External Connector type:access Bus (USB) Port type:usb Handle 0x000e, DMI Type 8, 9 bytes Port Connector information Internal Reference designator: J5A1 Internal Connector type:none External Reference designator:lan External Connector type:rj-45 Port type:networ K Port Handle 0x000f, DMI type 9, bytes System Slot information designation:j6b2 type:x16 PCI Express Current Us Age:in use Length:long id:0 characteristics:3.3 V are provided Opening is shared PME signal are supported bus address:0000:00:01.0 Handle 0x0010, DMI type 9, bytes System Slot information designation:j6b1 type:x1 PCI Expre SS Current Usage:in UsE length:short id:1 characteristics:3.3 V is provided Opening is shared PME signal are supported bus address: 0000:00:1c.3 Handle 0x0012, DMI type one, 5 bytes OEM Strings string 1:dell System String 2:5[0003] string 3:13[p18
 
F] Handle 0x0013, DMI type 5 bytes System Configuration Options Option 1:to be filled by O.E.M. Handle 0x001c, DMI type, 7 bytes built-in pointing Device type:touch Pad interface:bus Mouse buttons:2 Handle 0 x001d, DMI type, bytes portable Battery location:sys. Battery Bay Manufacturer:sanyo serial number:5390 Name:dell 4yrjh22 chemistry:lithium Ion design Capacity: 45000 mWh Design voltage:10800 mV sbds version:1.0 Maximum error:2% SBDs manufacture date:2012-02-28 Oem-spec
 
ific information:0x00000001 Handle 0x001e, DMI type (bytes System Boot information Status:no errors detected Handle 0x0020, DMI type bytes Cooling Device type:fan Status:ok oem-specific: 0x00000000 Handle 0x0021, DMI type, bytes temperature Probe description:cpu Internal temperature
 Ocessor Status:ok Maximum value:127.0 deg C Minimum value:0.0 deg C resolution:1.000 deg C tolerance:0.5 deg C Accuracy:unknown oem-specific information:0x00000000 Handle 0xb000, DMI type 176, 5 bytes oem-specific type Header A nd data:b0 B0 Handle 0xb100, DMI type 177, bytes oem-specific type Header and data:b1 0C B1 1 a 0E  Handle 0x0025, DMI Type 209, bytes oem-specific type Header and data:d1 0C 25 00 00 00 00 03 05 Handle 0x0026, DMI type 210, bytes oem-specific type Header and Data:d2 0C 26 00 00 00 00 03 05 20 01 0 3 Handle 0x0027, DMI type 211, bytes oem-specific type Header and Data:d3 0D (St) Rings:front Handle 0x0028, DMI type 212, bytes oem-specific type Header and DATA:D4 39 28 00 70 00 71 00 0
 9C FC (1 km) 9B FC 7F 4 A FB 4 a FB 4 a F7 4 a F7 7B a 4 a EF 7C 4 a EF FF FF 00, a-B          
 
Handle 0x002a, DMI type 217, 8 bytes oem-specific type Header and data:d9 2A Strings: Handle 0x002b, DMI type 219, bytes oem-specific type Header and data:db 0B 2B ' Strin Gs:handle 0x002c, DMI type, bytes oem-specific type Header and DATA:DC 2C 00 01  F0 F0 Handle 0x002d, DMI type 221, bytes oem-specific type Header and/F0) F0. Data:dd a Handle 0x002e, DMI type 222, bytes oem-specific T, in the same--- Ype Header and Data:de 2E, Handle 0x0014, DMI type, bytes physical Me, at the same Mory Array location:system Board Or motherboard use:system Memory Error correction type:none Maximum capacity:16 G B Error Information HanDle:not provided number of Devices:2 Handle 0x0016, DMI type, bytes Memory, Device mapped address starting Addr ess:0x00000000000 ending address:0x000ffffffff Range size:4 GB physical Device handle:0x0015 Memory Array mapped A ddress handle:0x0018 Partition Row position:1 interleave position:1 interleaved Data depth:1 Handle 0x0017, DMI t ype bytes Memory Device Array handle:0x0014 Error information handle:0x0000 total Width:unknown Data Width: Unknown size:no Module installed Form factor:dimm set:none locator:dimm_b Bank locator:bank 2 type:unknown Ty  PE detail:none speed:unknown manufacturer:not Specified serial number:not Specified Asset tag:not Specified part Number:not Specified rank:unknown Handle 0x0018, DMI type, bytes Memory Array mapped address starting address : 0x00000000000 ending address:0x000ffffffff Range size:4 GB physical Array handle:0x0014 Partition width:2 Hand Le 0x002f, DMI type 13,Bytes BIOS Language information Language Description format:abbreviated installable languages:1 Eng I nstalled Language:eng Handle 0x0030, DMI type 131, bytes oem-specific type Header and data:83 40 30 00 31 00 00 For F8 4 b 1C FF FF FF FF 00 00 0 For each of the C8 (a) of "a" for a. Handle 6F (0x0029), DMI type 216, 9 bytes oem-specific type Header An, at $0 d data:d8 strings:intel 0000 Handle 0x0000, DMI type 0, bytes BIOS information vend
 Or:dell INC. VERSION:A05 release date:08/03/2012 address:0xf0000 Runtime size:64 kb ROM size:2048 KB CHARACTERISTICS:MCA i s supported PCI is supported BIOS are upgradeable BIOS shadowing is allowed ESCD support are available Boot from C  D is supported selectable boot are supported BIOS ROM is socketed EDD is supported 5.25 "/1.2 MB Floppy services are Supported (int 13h) 3.5 "/720 KB Floppy services are supported (int 13h) 3.5"/2.88 MB Floppy services are supported (int 13h) Print screen service is supported (int 5h) 8042 keyboard services are supported (int 9h) serial services are Supporte d (int 14h) Printer services are supported (int 17h) Cga/mono Video services are supported (int 10h) ACPI is support  Ed USB Legacy is supported ATAPI ZIP drive boot are supported BIOS Boot specification is supported targeted content Distribution is supported BIOS revision:0.5 firmware revision:0.5 Handle 0x0002, DMI type 2, bytes Base Board in
 Formation Manufacturer:dell Inc. Product NAME:01HXXJ version:a05 serial number:. Jsq7pa1.
 Cn7117623m00j2. Asset Tag:not Specified Features:board is a hosting Board Board are replaceable Location in chassis:to be filled B
 Y o.e.m. Chassis handle:0x0003 Type:motherboard contained Object handles:0 Handle 0x0003, DMI Type 3, Bytes chassis infor Mation Manufacturer:dEll INC. Type:portable lock:not Present version:not Specified serial number:jsr1 Asset tag:not Specified boot-up state:s AFE Power Supply State:safe Thermal state:safe security Status:none OEM information:0x00000000 height:unspecifie  D number of power cords:1 contained elements:0 Handle 0x0001, DMI type 1, bytes System information manufacturer:
 Dell INC.  Product Name:inspiron N5050 version:not Specified serial NUMBER:JSR1 uuid:4c4c4544-0053-5110-8029-cac05241 Wake-up
 Type:power Switch SKU number:to is filled by O.E.M. Family:handle 0x0024, DMI type, bytes oem-specific type Header and data:d0 0C FE 00 04 05 strings:20120323 20120323 Handle 0x0011, DMI type 6 bytes on Board Device information Type:video Stat  us:enabled description:mobile Intel sandybridge HD Graphics Handle 0x0015 bytes, DMI type, Memory Device Array handle:0x0014 Error information handle:0x0000 Total width:64Bits Data width:64 bits size:4096 MB Form factor:sodimm set:none locator:dimm_a Bank locator:bank 0 type:ddr 3 Type detail:synchronous speed:1067 MHz manufacturer:014f serial number:0009f2 Asset tag:54114000 part Numbe
 r:jm1066-4g rank:unknown Handle 0x0031, DMI type 127, 4 bytes End of Table

Well, that's it.

via:http://www.unixmen.com/linux-basics-how-to-find-maximum-supported-ram-by-your-system/

Author: SK Translator: mr-ping proofreading: Wxy

This article is originally translated by Lctt