[X4U] Snow Leopard "seemingly" strange behavior

[Linda]

On 9/16/09 1:22 PM, James Bess wrote:

> Except, if I turn off my external hard-drive Snow
> Leopard is very, very slow to boot-up or close-down.  I have a new (purchased
> April 2009) 24" iMac with 4GB RAM.  I'm guessing that the slow performance
> when the external HD is switched off is due to either (1) this HD is set up
> with Time Machine, and/or (2) same HD is recipient for all SuperDuper backups?
> Are there any other possible explanations for slow performance?  Thanks!

Silly question: Do you unmount the hard disk before you switch off the
external disk?