A:Answer Hello stonecold,
To provide the RPM of the internal hard drive, we need the serial number of the external hard drive.
However rotational speed of the internal hard drive doesn't impact the transfer speed of the Seagate Backup Plus Hard Drive, since the expected performance depends on the USB cables and ports. For more information please check on the link below: https://www.seagate.com/support/kb/how-fast-should-an-external-drive-be-172213en/
Data sheets of the Backup Plus Driives
https://www.seagate.com/consumer/backup/backup-plus/#specs
Regards,
Zac
Seagate Support