I have heard that heat is bad for hard drives, but what exactly does it do that kills them? Also, what is the "safe range" for HD temps. The reason I ask is that I have now bought two laptops (one Dell and one Gateway) and neither have a HD cooling fan. In both, under heavy use the HD can reach 50C and feel hot to the touch. I bought chill pads for each which keeps them happily in the 30C-40C range (currently 37C), but why don't they put a little fan near the drive. Are they so obsessed with quietness that they would sacrific HD life? Or, is 50C an OK temp for HDs and thus there is no need (although it does get my leg a little warm). I have also noticed this lack of HD cooling on many Laptops of all brands in retail stores. I guess I am used to my Desktop HDs which have big 120mm fans keeping them in the low 30s under load.
if you exceed rated temperature specs of the individual hdd, you do risk damaging it, not just shortening its life (though i guess those can be considered synonymous)... youd need to find out what those specifics are from the manufacturer
in 2 of the hdds i had, overheating was the cause of failure, or similar (such as the hdd no longer being recognized)... one was an external usb 2.0 7200 40GB, which ended up losing data even as a result, ontop of the drive no longer being reliable now (my system would crash at random intervals when the hdd was attached after that)... the other was a 36GB GD raptor that i had hosted as an external usb 2.0 hdd, the raptor itself is still in working condition (no more problems after removing it from the case, i also scanned it afterwards for errors with WDs hdd utilities), but the case it was in blocked the ventilation chamber underneath, so there was no airflow then (didnt even realize till afterwards there was an area underneath that specifically says not to obstruct it, lol)
as far as specifically why heat is bad, i couldnt say... but i will say that when you have enough heat concentrated in a small area long enough, the hdd itself probably wont last long at all before you start experiencing hdd related problems. if you arent having any problems like described above, then the hdds are most likely operating inside safe parameters.
the only problem im seeing with the charts in regards to temperatures, is they seemed to stop guaging at a max of about 50C... and 60C 70C and 80C+ arent at all guaged then... those are also the temperatures that cpus can only tolerate up to usually too, before things start behaving sporadically (and they do, when things start getting hot enough)... ...but, under typical operating circumstances, and as long as the hdd is operating close to within spec, then heat usually isnt too much of an issue, even if the hdd itself feels hot. (which actually does coincide more with what theyre saying)
such as, western digitals hdds seem to be rated up to an operating temp of 55C, and 65C when not on... they should work just fine when theyre within those temperatures... ...but if you wander outside of that by a lot, yeah
from the google pdf... "In fact, there is a clear trend showing that lower
temperatures are associated with higher failure rates.
Only at very high temperatures is there a slight reversal
of this trend."
the high temperature reversal as they put it seems capable enough to damage hdds though, let alone beyond what they tested... which is usually an indication of incredibly poor ventilation in a highly heated surrounding area (not just the hdd itself being hot), literally a dry sauna (up to 77C+). which isnt quite enough to boil or really melt anything (aside from frozen stuff)