I bought a second SO-DIMM for my Dell Latitude 5420 and want to check if the RAM works in dual-channel mode now. Everyone suggests using dmidecode to figure this out, but my output differs from what other people have. But it also differs from single-channel-only laptop I had before, so I don't know how to interpet it. Can someone help? Here's the output of sudo dmidecode -t memory:
# dmidecode 3.3
Getting SMBIOS data from sysfs.
SMBIOS 3.2 present.
Handle 0x1000, DMI type 16, 23 bytes
Physical Memory Array
Location: System Board Or Motherboard
Use: System Memory
Error Correction Type: None
Maximum Capacity: 128 GB
Error Information Handle: Not Provided
Number Of Devices: 2
Handle 0x1100, DMI type 17, 92 bytes
Memory Device
Array Handle: 0x1000
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 16 GB
Form Factor: SODIMM
Set: None
Locator: DIMM B
Bank Locator: BANK 0
Type: DDR4
Type Detail: Synchronous
Speed: 3200 MT/s
Manufacturer: 01980000802C
Serial Number: CEB33182
Asset Tag: 07213400
Part Number: 9905744-077.A00G
Rank: 2
Configured Memory Speed: 3200 MT/s
Minimum Voltage: Unknown
Maximum Voltage: Unknown
Configured Voltage: 1.2 V
Memory Technology: DRAM
Memory Operating Mode Capability: Volatile memory
Firmware Version: Not Specified
Module Manufacturer ID: Bank 2, Hex 0x98
Module Product ID: Unknown
Memory Subsystem Controller Manufacturer ID: Unknown
Memory Subsystem Controller Product ID: Unknown
Non-Volatile Size: None
Volatile Size: 16 GB
Cache Size: None
Logical Size: None
Handle 0x1104, DMI type 17, 92 bytes
Memory Device
Array Handle: 0x1000
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 16 GB
Form Factor: SODIMM
Set: None
Locator: DIMM A
Bank Locator: BANK 0
Type: DDR4
Type Detail: Synchronous
Speed: 3200 MT/s
Manufacturer: 80AD000080AD
Serial Number: 2371A7C9
Asset Tag: 02211100
Part Number: HMAA2GS6AJR8N-XN
Rank: 1
Configured Memory Speed: 3200 MT/s
Minimum Voltage: Unknown
Maximum Voltage: Unknown
Configured Voltage: 1.2 V
Memory Technology: DRAM
Memory Operating Mode Capability: Volatile memory
Firmware Version: Not Specified
Module Manufacturer ID: Bank 1, Hex 0xAD
Module Product ID: Unknown
Memory Subsystem Controller Manufacturer ID: Unknown
Memory Subsystem Controller Product ID: Unknown
Non-Volatile Size: None
Volatile Size: 16 GB
Cache Size: None
Logical Size: None
As you can see, the sticks are in one bank, but in different locators. Does that mean they're running in single-channel, or dual-channel mode? Or is there some other way to find this out?
Edit: The BIOS photo - well, that was easy. Thanks, Dell! And Mokubai, of course, for pointing me to an obvious solution :)