[dba-Tech] External Hard Drive

I have an external HD that I use with Ghost 9.0 as a backup device.  The
disk is a 60 Gb laptop disk in a Nexstar case.  This is USB powered, and is
fairly nice.

All went well until I changed from a 4 port D-link hub to a 7 port D-link
hub.  Now, when my laptop powers up automatically at 5 AM to run the backup
program, the laptop can't find the external HD (it did before).  Once I
unplug and reattach the USB cables to the HD, the laptop will then recognize
the external HD, and I can start the backup program.

Also, once the HD is recognized, I can tell from the flashing light that the
laptop is constantly trying to write to the HD, although it doesn't write
anything and there are no programs running that should cause this.  And,
when I was previously connected through the 4 port hub, the light was a
solid green.

I wouldn't think that a change in USB hubs would actually trigger this.  But
what could cause this problem?

Thanks!
Dan