Altitude?

[Robert Love]

On Sep 4, 2007, at 8:43 PM, Hacker Scot wrote:

> Just noticed something in the iMac tech specs, alongside min/max  
> voltage, etc:
>
> - Maximum altitude: 10,000 feet
>
> ??? What components in a computer are altitude sensitive?
>
> Not that I plan to take my Mac up Everest any time soon... just  
> morbid curiosity.

Are hard drives sealed against outside air?  I remember reading about  
mountaineers buying multiple iPods and by trial and error, finding  
ones that worked well up Everest.