I have a 150gig Raptor. Can barely stand the thing compared to modern 7200s. However, I have had 7200s that were louder than a Raptor.
And it wasn't just seek noise, but dental-drill esque ball bearing whine. OMG, I can not deal with that noise anymore.
To solve the seek vibration of HDDs, I pondered options deeply, and pondered ways to avoid overpriced commercial solutions. I went out to the fabric store and got some elastic cording. I wrap the stuff around inside the drive bay and make a sort of web for the HDD to sit in. You obviously need to have open space in the bay to do this, so the bay needs to be a rail-style one. This mechanically disconnects the drive from the case and basically eliminates the transfer of vibration energy. It makes an
incredible difference. The Raptor 150 becomes quieter than the unsilenced WD 500gigs in the comp next to it. Muffled clicking is all that is left of the usually case-rattling seeks. This simple method has worked better than any built-in dampening design that I've messed with and no elastic has broken in the years I've been doing this. Watch out though: the ladies at those fabric stores can be rather unaccepting of male invaders who are clueless about how to buy their goods. Bring a female escort, perhaps.