A:Answer Hello JBK,
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 Expansion, since the expected performance depends on the USB cables and ports. For more i information please check on the link below:
https://www.seagate.com/support/kb/how-fast-should-an-external-drive-be-172213en/
Regards,
Zac
Seagate Support