I suggest you connecting the Intel® SSD to the Intel® Chipset / SATA controller (usually SATA port 0, consult your system's documentation). If you are trying to connect the drive via USB, please make sure the Intel® SSD 520 is properly identified as such and not detected as a generic USB/SATA drive; otherwise you may need to change the USB adapter cable.
There is the possibility that another peripheral interferes with the process. You may want to disconnect other devices or connecting the keyboard and mouse to USB 2.0 ports.
Intel® High Performance Solid-State Drives — Data Migration FAQs