HDD to SSD slow transfer using SATA to USB3 cable (somewhat solved)

As just about everyone else I am switching my hard drive to an SSD.
Purchased the Samsung 850 EVO 1TB 2.5-Inch SATA III Internal SSD (MZ-75E1T0B/AM). That all arrived well.
Also then bought a Sabrent cable, SATA to USB 3.0 (under $10).
The problems started occurring when I was cloning the drives using Samsung’s Data Migration Software.
Note : My existing drive (SATA II internal) has been showing errors when using various HD inspection tools so that is one possible cause of slowness. It was also becoming very slow during general operation which was the reason to switch to SSD.

  1. I was cloning approximately 670GB of data on 931TB drive
  2. On the initial attempt transfer rate was 1MB/s. The estimate was 300+ hours to complete so I aborted that.
  3. I then plugged the cable into the USB 2.0 port. That produces speeds around 25MB/s but still very slow
  4. Then I switched back to plugging it into the USB 3.0 port. This time, speeds got up to 59MB/s and the promised completion time was under 4 hours which is acceptable. However, half way through it slowed down to 1MB/s and I had to cancel.
  5. Following some online research I proceeded to: disable Microsoft real time virus protection, disconnected the network drives that were mounted and also disconnected the Ethernet cable from the PC completely diabling networking.
  6. That worked. Speeds were again near 60MB/s and the clone took under 3.5 hours. Success.

I do know that USB 3.0 should provide higher transfer rates, but at this point I was just happy to get this done. I did not have time to investigate more.