[NTLK] OT: iPod hard drive blue foam, does one need it?

[Mr Jonathan Dueck]

Dear Newton list,

Soon I'll have a Surface Pro (which should let me try out Einstein again)! But in the meantime I'm occupying myself with the revival of an old iPod 4th Gen 20gb, which I suspected some other listserv members might've done. 

I opened the case and swapped out the hard drive, no problem, and the unit appears to be working great. The blue "bumpers" that go around the drive transferred easily. But I didn't have a razor or other sharp, flat scraper handy, and the blue foam on the bottom of the old hard drive just came apart when I tried to take it off. The unit appears to work fine without the foam.

So I'm wondering: what does that foam do? Googling yields answers like "I don't know," and "It's important for ariflow" which seems counterintuitive. Does anyone on Newtontalk know? If the answer is "well it might marginally improve the life of your hard drive because it'll keep it a little cooler" then I will probably just leave it; if the answer is "you're going to start a fire with that thing!" I'll try to find a substitute for the foam. 

Cheers,
Jon