Well it's never really been proven, but it's the general concensus that if you use some sort of cooling device on your super-fast HD, then you can potentially help it last longer.
I mean, 7200RPM (and fast SCSI HD's) is really fast. Speed like that tends to heat up the HD, and the components inside of it do not appreciate heat. When things get hot, they Expand. And when they cool down, they Contract. Constant expanding and contracting will eventually wear it out. So if you have 'some' cooling on the HD, at least it will not Expand as much as it would if it didn't have cooling. So it's kinda like:
Without Cooling: EXPAND.contract.EXPAND.contract.EXPAND.contract...
With Cooling: expand.contract.expand.contract.expand.contract...
The change isn't quite as drastic, so the components won't get tortured as much -- and will thank you by lasting a bit longer! hehe. Cooling is just an insurance factor. You get it to hopefully prevent/delay/protect from the inevitable. You can backup all you want, but your HD will crap out on you one day. So better to have it later than sooner...
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JV
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