USB bit rate and byte transfer rate

[engr_joni_ee]

USB 3.0 has bit rate 5.0 Gbits/s but in my computer when I transfer the data from internal hard drive to external USB 3.0 drive. The data is transferring at the 100 MByte per second or less. It look like around 50 bits per byte ?

5000 Mbits / 50 = 100 M Byte

Is is that much for implementing USB protocol and packet formation ?

 

[FvM]

You know that hard drives have maximal read and write speed?

 

[engr_joni_ee]

Oh yes that could be the limit on data transfer. The read/write speed of the drive. I am having SSD drive with transfer data speed around 300 M Bytes per second.

But in general how much M bytes per second we can send over USB 3.0 including packets headers.

 

[FvM]

For Gen1 (5 GBPS), I would expect up to 480 MB/s. Depends if the PC driver stack is able to pass it.