. I recently bought a Silverstone Berserker case (my review here: http://www.techimo.com/reviews/ ) and found that the top panel was made of thinner material and was totally undamped. The result is that the thing rings like a bell as it comes from the factory. I used random lengths of rope caulk (Mortite and FrostKing are two brand names) on the bottom side of the panel and now it is sutably dead. We used to use it in the olden audiophile days for damping turntables (for the kiddees, turntables were used to play vinyl redords - pre CD era...).
. As has been explained in several of the articles, damping the panels usually has little effect on the overall noise of a system - but it made me feel better and didn't cost much at all (I always have the stuff on hand anyway - uses are many). Not pretty, but can be covered where necessary.
. Hope some may find this useful.
.bh.