My Xbox 360 is just so loud, I can't stand using it. It's like a vacuum cleaner when it's going all out. So I'm either going to sell it, or I'm going to rip the mother apart and replace the case fans in it with some ultra quiet ones I can buy online or down at Fry's. Check out this article at AnandTechwhere they disassemble the 360 - you can see where the noise is coming from: There's no on-chip fans, just two big-ass case fans in the back of the box which circulate air with the help of a shroud that sits over the cpu and gpu. Seems like you could rip those things out of there with no problem...
I have no idea what I'm doing, so of course I'm going to say something like that.
I saw the "water-cooled" mods that were floating around recently, and that just doesn't do it for me. I don't want to mess with tubes and all that, I just want the box to be quiet. I tested it out by sticking some pens in the back while it was running (carefully of course), the fans are really the main source of the noise. The power brick hums a bit and has it's own quiet fan, the HD makes little buzzing sounds once in a while, and the DVD does that clicking/clanking thing DVDs can do, but the case fans are the really loud bits. There's two distinct noises they make - a whirring noise (which is really what gets me most) and the sound of the air moving through the vents. I don't think much can be done about the latter except maybe cutting two big holes in the back so there's no grating, but the whirring noise needs to go.
I definitely have to do it right, because I noticed that after just a couple minutes of being down behind the console listening to it, I could feel the air being pumped out heating up considerably. It's like a low-powered hair dryer back there! Seriously! So it's not something where you throw in some underpowered fans and say job well done. They've got to move air.
Okay, a few issues. First, there doesn't seem to be any real info about replacing fans on the new Xbox 360 out there, so I was looking at some of the fan mods for the old Xbox and noticed that there's a 12V adapter being sold. I can see through the grating that the new fans are marked with the same voltage. So that's First. Secondly, the fans are custom made to fit into the box and fit together snugly - and I'm not sure what size they are. The ultra-quiet case fans I've found online are like 70mm and 80mm, so I'm not sure what to do. It seems I'm going to have to rip the box open first, extract the fans, and then go down to the store with the part in hand so I can compare. If I end up not finding what I need, then I've just violated the warranty and made the whole thing less resaleable for nothing... so I'm thinking about what to do carefully.
The other option is to just sell the thing and forget about it. Man it's loud.
P.S. Here's a .wav sound file of the 360 getting turned on. I put the mike behind the box at first, but the wind noise was so loud no one would believe me, so I moved it to the side. :-)