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A single-lane (x1) PCIe v. 2.x link offers a maximum throughput of:

A. 125 MB/s
B. 250 MB/s
C. 500 MB/s
D. 985 MB/s
E. 1969 MB/s

1 Answer

2 votes

Final answer:

A single-lane (x1) PCIe v. 2.x link provides a maximum throughput of 500 MB/s, factoring in the encoding overhead from its 5 GT/s rate.

Step-by-step explanation:

The question concerns the bandwidth capabilities of the PCIe (Peripheral Component Interconnect Express) interface, specifically the version 2.x. A single-lane (x1) connection on PCIe version 2.x offers a maximum theoretical throughput of 500 MB/s. This is due to the fact that PCIe 2.x transmits data at a rate of 5 GT/s (GigaTransfers per second), and after encoding overhead, which takes about 20%, the data rate results in 4 GT/s effective data transfer rate. Since each transfer carries 8 bits of data, the calculation for the throughput is: 4 GT/s × 8 bits/transfer = 32 Gb/s. When converted to bytes, this becomes 32 / 8 = 4 GB/s for the entire bus. However, since we're discussing a single lane (x1), the throughput is 1/8th of the total, hence 500 MB/s.

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