I recently purchased a laptop to install ubuntu onto. From my understanding, there is 1 SSD inside with a size of 256GB. However, upon attempting to install ubuntu, I am given two partitions, SDA and SDB of equal size.

If I install on SDA will that limit my "total" size of ubuntu to 128 GB? How do I combine the two to use a total size of 256 GB?

Am I wrong in assuming that there is 1 SSD of size 256?

Thank you.

@falconer's request

/dev/sda:

ATA device, with non-removable media

    Model Number:       SanDisk SD6SP1M128G1002                

    Serial Number:      132254401865       

    Firmware Revision:  X231202

    Media Serial Num:  

    Media Manufacturer:

    Transport:          Serial, ATA8-AST, SATA 1.0a, SATA II Extensions, SATA Rev 2.5, SATA Rev 2.6, SATA Rev 3.0

Standards:

    Used: unknown (minor revision code 0x0028)

    Supported: 8 7 6 5

    Likely used: 8

Configuration:

    Logical        max    current

    cylinders    16383    16383

    heads        16    16

    sectors/track    63    63

    --

    CHS current addressable sectors:   16514064

    LBA    user addressable sectors:  250069680

    LBA48  user addressable sectors:  250069680

    Logical  Sector size:                   512 bytes

    Physical Sector size:                   512 bytes

    Logical Sector-0 offset:                  0 bytes

    device size with M = 1024*1024:      122104 MBytes

    device size with M = 1000*1000:      128035 MBytes (128 GB)

    cache/buffer size  = unknown

    Nominal Media Rotation Rate: Solid State Device

Capabilities:

    LBA, IORDY(can be disabled)

    Queue depth: 32

    Standby timer values: spec'd by Standard, no device specific minimum

    R/W multiple sector transfer: Max = 1    Current = 1

    Advanced power management level: 128

    DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5 *udma6

         Cycle time: min=120ns recommended=120ns

    PIO: pio0 pio1 pio2 pio3 pio4

         Cycle time: no flow control=120ns  IORDY flow control=120ns

Commands/features:

    Enabled    Supported:

       *    SMART feature set

            Security Mode feature set

       *    Power Management feature set

       *    Write cache

       *    Look-ahead

       *    Host Protected Area feature set

       *    WRITE_BUFFER command

       *    READ_BUFFER command

       *    DOWNLOAD_MICROCODE

       *    Advanced Power Management feature set

            SET_MAX security extension

       *    48-bit Address feature set

       *    Device Configuration Overlay feature set

       *    Mandatory FLUSH_CACHE

       *    FLUSH_CACHE_EXT

       *    SMART error logging

       *    SMART self-test

       *    General Purpose Logging feature set

       *    64-bit World wide name

       *    WRITE_UNCORRECTABLE_EXT command

       *    {READ,WRITE}_DMA_EXT_GPL commands

       *    Segmented DOWNLOAD_MICROCODE

       *    Gen1 signaling speed (1.5Gb/s)

       *    Gen2 signaling speed (3.0Gb/s)

       *    Gen3 signaling speed (6.0Gb/s)

       *    Native Command Queueing (NCQ)

       *    Host-initiated interface power management

       *    Phy event counters

       *    READ_LOG_DMA_EXT equivalent to READ_LOG_EXT

       *    DMA Setup Auto-Activate optimization

            Device-initiated interface power management

       *    Software settings preservation

       *    Device Sleep (DEVSLP)

       *    Data Set Management TRIM supported (limit 16 blocks)

       *    Deterministic read ZEROs after TRIM

Security:

    Master password revision code = 65534

        supported

    not    enabled

    not    locked

        frozen

    not    expired: security count

        supported: enhanced erase

    2min for SECURITY ERASE UNIT. 12min for ENHANCED SECURITY ERASE UNIT.

Logical Unit WWN Device Identifier: 5001b449d68f0149

    NAA        : 5

    IEEE OUI    : 001b44

    Unique ID    : 9d68f0149

Checksum: correct

Device Sleep:

    DEVSLP Exit Timeout (DETO): 20 ms (drive)

    Minimum DEVSLP Assertion Time (MDAT): 10 ms (drive)



/dev/sdb:



ATA device, with non-removable media

    Model Number:       SanDisk SD6SP1M128G1002                

    Serial Number:      132254404902       

    Firmware Revision:  X231202

    Media Serial Num:  

    Media Manufacturer:

    Transport:          Serial, ATA8-AST, SATA 1.0a, SATA II Extensions, SATA Rev 2.5, SATA Rev 2.6, SATA Rev 3.0

Standards:

    Used: unknown (minor revision code 0x0028)

    Supported: 8 7 6 5

    Likely used: 8

Configuration:

    Logical        max    current

    cylinders    16383    16383

    heads        16    16

    sectors/track    63    63

    --

    CHS current addressable sectors:   16514064

    LBA    user addressable sectors:  250069680

    LBA48  user addressable sectors:  250069680

    Logical  Sector size:                   512 bytes

    Physical Sector size:                   512 bytes

    Logical Sector-0 offset:                  0 bytes

    device size with M = 1024*1024:      122104 MBytes

    device size with M = 1000*1000:      128035 MBytes (128 GB)

    cache/buffer size  = unknown

    Nominal Media Rotation Rate: Solid State Device

Capabilities:

    LBA, IORDY(can be disabled)

    Queue depth: 32

    Standby timer values: spec'd by Standard, no device specific minimum

    R/W multiple sector transfer: Max = 1    Current = 1

    Advanced power management level: 128

    DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5 *udma6

         Cycle time: min=120ns recommended=120ns

    PIO: pio0 pio1 pio2 pio3 pio4

         Cycle time: no flow control=120ns  IORDY flow control=120ns

Commands/features:

    Enabled    Supported:

       *    SMART feature set

            Security Mode feature set

       *    Power Management feature set

       *    Write cache

       *    Look-ahead

       *    Host Protected Area feature set

       *    WRITE_BUFFER command

       *    READ_BUFFER command

       *    DOWNLOAD_MICROCODE

       *    Advanced Power Management feature set

            SET_MAX security extension

       *    48-bit Address feature set

       *    Device Configuration Overlay feature set

       *    Mandatory FLUSH_CACHE

       *    FLUSH_CACHE_EXT

       *    SMART error logging

       *    SMART self-test

       *    General Purpose Logging feature set

       *    64-bit World wide name

       *    WRITE_UNCORRECTABLE_EXT command

       *    {READ,WRITE}_DMA_EXT_GPL commands

       *    Segmented DOWNLOAD_MICROCODE

       *    Gen1 signaling speed (1.5Gb/s)

       *    Gen2 signaling speed (3.0Gb/s)

       *    Gen3 signaling speed (6.0Gb/s)

       *    Native Command Queueing (NCQ)

       *    Host-initiated interface power management

       *    Phy event counters

       *    READ_LOG_DMA_EXT equivalent to READ_LOG_EXT

       *    DMA Setup Auto-Activate optimization

            Device-initiated interface power management

       *    Software settings preservation

       *    Device Sleep (DEVSLP)

       *    Data Set Management TRIM supported (limit 16 blocks)

       *    Deterministic read ZEROs after TRIM

Security:

    Master password revision code = 65534

        supported

    not    enabled

    not    locked

        frozen

    not    expired: security count

        supported: enhanced erase

    2min for SECURITY ERASE UNIT. 12min for ENHANCED SECURITY ERASE UNIT.

Logical Unit WWN Device Identifier: 5001b449d68f0d26

    NAA        : 5

    IEEE OUI    : 001b44

    Unique ID    : 9d68f0d26

Checksum: correct

Device Sleep:

    DEVSLP Exit Timeout (DETO): 20 ms (drive)

    Minimum DEVSLP Assertion Time (MDAT): 10 ms (drive)

@RPiAwesomeness

As you can see,
/dev/sda is in the top right corner in the drop down menu, /dev/sdb can be accessed from there as well.