Ok.
If you don't like what you hear? I say invest in more quiet fans like Noctua or Nexus for example. You want at least 35 cfm air flow with the silent fans you pick. And a max rpm between 1200 - 1600.
The Noctua fans are my favourite brand. Cost some more, but are well worth it. I have had 2 of them as exhaust ( 1 at the back and one at the top ). for 5 years now and they never have missed a beat. And in the winter, when the ambient temperatures are lower. I only run them at 1000 rpm. They cool well enough at that speed too. The only thing I hear from the box are the slight hizzing of air rushing into the case. The case sits just 1 meter from me at the top of the computer desk. The MSI Gaming series of videocards are very quiet too even at load. The Asus Direct CU series and the Gigabyte cards are quiet too. But in that area MSI, beats them by a bit when at load.
I did'nt notced yesterday that the 2 x top exhaust fans in the Thermaltake case where optional. Sorry about that. Yes, there you have another dust intake / noise amplifer. But get at least 1 silent 120mm for the top anyway. This as much of the warm / hot air from the hardware, will travel upwards in the case. And if you have / get a cpu cooler wich backside are facing the top of the case? A top exhaust fan or 2 will be good for obvious reasons. And then per automatic you will have a kind of push - pull, cpu to case fan configuration too.
It's also a smart move to mount the fans with rubber grommits or round, elastic cords to dampen vibrations between the fan and the case. You can even put a small amount of Blue Tack or Play Dooh at the corners of the fan houseing, facing the case, to further improve the noise levels. The Noctua fans comes with houseing, rubber dampers and grommits though.
There are two good ways to make a non SSD harddrive to run more silent. Get some silicone hdd vibration dampers, wich should be mounted beween the hdd and the hdd bracket. Do not tighten the screws all the way though! That will destroy the whole idea with the dampers. You can also suspend the hdd in mid air using elastic cords of a sturdier kind.
http://www.silentpcreview.com/article8-page2.html
