I'm not aware of any issues that would manifest themselves.
As a new computer, your DELL is most likely to have USB 2.0 ports but its worth checking.
Most external drives have USB 2.0 connections which would match your DELL's USB 2.0 ports.
Some external drives also have Firewire 400 or even 800 connections. Obviously to be able to use these, your DELL would also have to have the equivalent Firewire 400 or 800 which is rare.
I use a USB 2.0 external harddrive without any issue on 2 Evesham, 1 MESH and 1 Sony, which are 1 - 5 years vintage.