What does x16 denote in PCIe lane configurations?

• A. A single data channel.
• B. 16 lanes providing higher bandwidth.
• C. A 16-bit data path.
• D. Sixteen physical lanes used together for increased bandwidth.

Answer: (D)

PCIe uses a scalable, high-speed serial interface. The xN notation shows how many physical lanes form one link. Each lane is a separate serial channel, and the lanes operate in parallel to boost total bandwidth. So x16 means sixteen lanes are bonded to work together as a single PCIe link, giving much more bandwidth than a single lane. The actual speed per lane depends on the PCIe generation (Gen 3, Gen 4, Gen 5), but the core idea is that sixteen lanes are used together to carry data. This is different from a 16-bit data path, since PCIe lanes carry serial data, not a single wide 16-bit parallel bus. A single data channel describes a single-lane link, which is not what x16 represents.