Yeah several members have had issues with external drives running on 5400rpm so it's pretty possible.
perfectly possible with 5400 rpm HDD especial if its connect to USB running USB1.0. 2.0-3.0 and 7800rpm HDD should have no problems
Well, I'm definitely running the 5400 rpm. I mean, there are some times when the game just completely stops for a couple seconds, the white light on the external flashes for a second, then the game resumes, so I'm assuming that the external is to blame in those cases.
usb can be a bit of a thorn in the side when running games of external drives, more than the drive speed itself being the problem. It is best to run them internally.
Good to know about these issues, I'm in the verge to buy an external HD and in doubt about getting an e-SATA or USB.