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OpenCore Configuration

Memory Properties

  1. DataWidth
    • Type: plist integer, 16-bit
    • Failsafe: 0xFFFF (unknown)
    • SMBIOS: Memory Device (Type 17) - Data Width
    • Description: Specifies the data width, in bits, of the memory. A DataWidth of 0 and a TotalWidth of 8 indicates that the device is being used solely to provide 8 error-correction bits.
  2. Devices
    • Type: plist array
    • Failsafe: Empty
    • Description: Specifies the custom memory devices to be added.

    To be filled with plist dictionary values, describing each memory device. Refer to the Memory Devices Properties section below. This should include all memory slots, even if unpopulated.

  3. ErrorCorrection
    • Type: plist integer, 8-bit
    • Failsafe: 0x03
    • SMBIOS: Physical Memory Array (Type 16) - Memory Error Correction

    • Description: Specifies the primary hardware error correction or detection method supported by the memory.

    • 0x01 - Other
    • 0x02 - Unknown
    • 0x03 - None
    • 0x04 - Parity
    • 0x05 - Single-bit ECC
    • 0x06 - Multi-bit ECC
    • 0x07 - CRC
  4. FormFactor
    • Type: plist integer, 8-bit
    • Failsafe: 0x02
    • SMBIOS: Memory Device (Type 17) - Form Factor
    • Description: Specifies the form factor of the memory. On Macs, this should typically be DIMM or SODIMM. Commonly used form factors are listed below.

    When CustomMemory is false, this value is automatically set based on Mac product name. When Automatic is true, the original value from the the corresponding Mac model will be set if available. Otherwise, the value from OcMacInfoLib will be set. When Automatic is false, a user-specified value will be set if available. Otherwise, the original value from the firmware will be set. If no value is provided, the failsafe value will be set.

    • 0x01 - Other
    • 0x02 - Unknown
    • 0x09 - DIMM
    • 0x0D - SODIMM
    • 0x0F - FB-DIMM
  5. MaxCapacity
    • Type: plist integer, 64-bit
    • Failsafe: 0
    • SMBIOS: Physical Memory Array (Type 16) - Maximum Capacity
    • Description: Specifies the maximum amount of memory, in bytes, supported by the system.
  6. TotalWidth
    • Type: plist integer, 16-bit
    • Failsafe: 0xFFFF (unknown)
    • SMBIOS: Memory Device (Type 17) - Total Width
    • Description: Specifies the total width, in bits, of the memory, including any check or error-correction bits. If there are no error-correction bits, this value should be equal to DataWidth.
  7. Type
    • Type: plist integer, 8-bit
    • Failsafe: 0x02
    • SMBIOS: Memory Device (Type 17) - Memory Type

    • Description: Specifies the memory type. Commonly used types are listed below.

    • 0x01 - Other
    • 0x02 - Unknown
    • 0x0F - SDRAM
    • 0x12 - DDR
    • 0x13 - DDR2
    • 0x14 - DDR2 FB-DIMM
    • 0x18 - DDR3
    • 0x1A - DDR4
    • 0x1B - LPDDR
    • 0x1C - LPDDR2
    • 0x1D - LPDDR3
    • 0x1E - LPDDR4
  8. TypeDetail
    • Type: plist integer, 16-bit
    • Failsafe: 0x4
    • SMBIOS: Memory Device (Type 17) - Type Detail

    • Description: Specifies additional memory type information.

    • Bit 0 - Reserved, set to 0
    • Bit 1 - Other
    • Bit 2 - Unknown
    • Bit 7 - Synchronous
    • Bit 13 - Registered (buffered)
    • Bit 14 - Unbuffered (unregistered)

Memory Device Properties

  1. AssetTag
    • Type: plist string
    • Failsafe: Unknown
    • SMBIOS: Memory Device (Type 17) - Asset Tag
    • Description: Specifies the asset tag of this memory device.
  2. BankLocator
    • Type: plist string
    • Failsafe: Unknown
    • SMBIOS: Memory Device (Type 17) - Bank Locator
    • Description: Specifies the physically labeled bank where the memory device is located.
  3. DeviceLocator
    • Type: plist string
    • Failsafe: Unknown
    • SMBIOS: Memory Device (Type 17) - Device Locator
    • Description: Specifies the physically-labeled socket or board position where the memory device is located.
  4. Manufacturer
    • Type: plist string
    • Failsafe: Unknown
    • SMBIOS: Memory Device (Type 17) - Manufacturer
    • Description: Specifies the manufacturer of this memory device.

    For empty slot this must be set to NO DIMM for macOS System Profiler to correctly display memory slots on certain Mac models, e.g. MacPro7,1. MacPro7,1 imposes additional requirements on the memory layout:

    • The amount of installed sticks must one of the following: 4, 6, 8, 10, 12. Using any different value will cause an error in the System Profiler.
    • The amount of memory slots must equal to 12. Using any different value will cause an error in the System Profiler.
    • Memory sticks must be installed in dedicated memory slots as explained on the support page. SMBIOS memory devices are mapped to the following slots: 8, 7, 10, 9, 12, 11, 5, 6, 3, 4, 1, 2.
  5. PartNumber
    • Type: plist string
    • Failsafe: Unknown
    • SMBIOS: Memory Device (Type 17) - Part Number
    • Description: Specifies the part number of this memory device.
  6. SerialNumber
    • Type: plist string
    • Failsafe: Unknown
    • SMBIOS: Memory Device (Type 17) - Serial Number
    • Description: Specifies the serial number of this memory device.
  7. Size
    • Type: plist integer, 32-bit
    • Failsafe: 0
    • SMBIOS: Memory Device (Type 17) - Size
    • Description: Specifies the size of the memory device, in megabytes. 0 indicates this slot is not populated.
  8. Speed
    • Type: plist integer, 16-bit
    • Failsafe: 0
    • SMBIOS: Memory Device (Type 17) - Speed
    • Description: Specifies the maximum capable speed of the device, in megatransfers per second (MT/s). 0 indicates an unknown speed.