Detecting memory type on FreeBSD

If you need to upgrade your RAM on a Windows machine, you can just use the Crucial Memory Advisor wotsit, which scans your computer using the power of, er, power to find out what your motherboard is, what RAM you already have, and then can tell you which overpriced Crucial RAM to buy.

On FreeBSD, this doesn’t work so well. However, you can tell manually tell the Crucial site what motherboard you have and it will tell you exactly what sort of RAM is best.

This is fine if you know what motherboard you have.

if you don’t, the answer is dmidecode(8) (/usr/ports/sysutils/dmidecode). This utility grabs the same information which the Crucial thingy does, so all you need to do is find the info you need.

This is pretty easy:

# dmidecode -t baseboard
SMBIOS 2.3 present.

Handle 0x0002, DMI type 2, 8 bytes
Base Board Information
        Manufacturer: ABIT <http ://www.abit.com.tw>
        Product Name: 694X-686B (VP6)
        Version: v1.0 ~
        Serial Number:

Not masses of useful information returned from my old system, but still enough to identify the motherboard as an Abit VP6. This is all I need to know to find out what memory I should be buying.

I already know what size sticks of RAM I have, but just incase you need to check:

# dmidecode -t memory
SMBIOS 2.3 present.
...
Handle 0x0021, DMI type 17, 21 bytes
Memory Device
    Array Handle: 0x0020
    Error Information Handle: Not Provided
    Total Width: Unknown
    Data Width: Unknown
    Size: 512 MB
    Form Factor: DIMM
    Set: None
    Locator: BANK_0
    Bank Locator: Bank0/1
    Type: Unknown
    Type Detail: None

Again, not the most useful information ever seen, but enough to tell me I have a 512MB stick in bank 0. (On my newer desktop, I get much more useful information like the speed and voltage of the RAM.)