Maximum Altitude: 10,000 Feet

Your daily dose of seldom-used tech trivia: Checking out the specs on the new iMacs, noticed a one-liner at the bottom of the Electrical and environmental requirements:

Maximum Altitude: 10,000 Feet

Not sure whether this is new to the new iMacs – I’ve just never noticed the stipulation before. So… what computer components are altitude-sensitive? Floated this question to a mailing list I’m on and got back some good theories, such as the fact that thinner air doesn’t circulate as well, and therefore lacks the cooling power of air at lower altitudes. Another respondent noted that mountaineers scaling Everest had purchased multiple iPods to find one that kept working all the way to the top (apparently some do, others don’t).

Found the most plausible explanation in a thread at Metafilter:

Specifically, the altitude concern is for the operation of the hard drive. Above a certain altitude, the low air pressure will allow the drive’s heads to scrape against the platters when in use, resulting in physical damage and data loss.

Larn something every day…

Music: Nick Lowe :: I Must Be Getting Over You

One Reply to “Maximum Altitude: 10,000 Feet”

  1. Haven’t followed the link to the other thread, but I design spacecraft by day (and fight for justice by night). The hard drive theory is an interesting one (half the mass of the atmosphere is below 14,000 feet), but I kind of doubt it’s a problem at 10K, have seen many spinning platter applications higher than that (though they definitely wouldn’t work in hard vacuum). My guess is that it’s electrolytic capacitors, they have a liquid component which is subject to vapor pressure, and will “dry out” faster under heat, low humidity, and especially altitude. Different types of caps can be substituted, but are more expensive especially for the relatively large sizes found in switching power supplies. Even here in Colorado, I’ve noticed consumer equipment having a much shorter lifetime than at sea level because the power supplies get noisy. Enjoy all that air you have at sea level! =)

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