Well, it started off as a cheap project, but then I wanted bigger hard drives, then I blew up my graphics card, so it all adds up in the end!!

Anyway, you can see the full story here: http://seanwright.pwp.blueyonder.co.uk/pcsilencing/

Enjoy, and if you have any tips or suggestions (other than the obvious "tidy up those wires!") I'd be glad to hear from you.

I've posted a reply to another thread, which I thought I'd copy over here as it is relevant to this thread too:

I haven't done much experimenting yet but I've formulated a few ideas recently. My current idea is to duct/shroud the intake/exhaust air for the CPU to keep it completely separate from the rest of the case (we're talking serious ghetto here, note the "on the cheap" comment on my web page!! )

There are a few pictures of my current setup here and you can see I've already got square cardboard intake duct. I'm planning to replace it with an 80mm round cardboard tube, which should interfere with the case exhaust fan less than the square one.

I'm also planning on constructing a cardboard shroud similar to Spydercat's (his first one) to exhaust all the CPU air through the PSU. I've already opened up the bottom of the PSU completely just above the CPU (as well as replacing that nasty Titan with a Panaflo) and I've got a temp controlled Panaflo exhausting the PSU. This should keep the internal case temp down, so I can slow the intake and exhaust fans down and still keep the other components cool.

The idea is to separate the cooling into two distinct airflows, so they are not competing with each other: a low airflow going through the case cooling the HDDs, graphics card ane memory etc, and a more concentrated temp controlled (and probably higher) airflow cooling the CPU and PSU.

That's the theory anyway. I'll be reporting my findings back here when I've done this, and see what it does to my PC temps/noise!!

You could try using vinyl dryer duct for your CPU duct. I got 8 feet for $5 at the hardware store, but I understand your desire to keep this project as cheap as possible, so you might be working under the mantra that any spending that can be avoided should be avoided.

Dryer duct is nice because its spiral support ring fits almost perfectly over the flanges of an 80mm fan, and it's collapsible, so you could snugly fit it from the CPU fan to the side of the case and still be able to open your case.

I really like what you've done so far with your project! Good luck with it.

I've thought about using dryer duct, and no I'm not too cheap to spend $5 or so, but apparently the uneven "ribbed" surface inside can cause turbulence and impede airflow. But maybe I'm just being too obsessive about it!

no your right pangit. i just had to replace my dryer duct and it looks as if it would really impede airflow.

Good point--I've been using dryer duct for a few weeks, and I thought the ruffly surface would provide some kind of damping! I think your explanation makes more sense. I'll have to do an experiment to see how much extra noise is added by using the duct.

By the way, I didn't mean to imply that you're cheap, I just meant that I understand the fun of silencing on a shoestring budget. I only bought my dryer duct because my complex labyrinth of paper ducting (made with an Army promotional mailer) kept falling apart.

Oh, and I forgot to mention in my first post that the green case is totally awesome!

I did a quick test with a low-speed NMB fan (with equivalent airflow to 6-7V Panaflo L1a) and some dryer duct. The duct attenuates high frequencies, which helps with the clicky fan, but it boosts lower frequencies, and it especially amplifies the airflow noise when the duct is collapsed instead of expanded. The nice thing is that, depending on the length of the duct, you can "tune" the airflow noise to be in a less-audible frequency.

With a 12V Panaflo L, the airflow noise will likely be much worse with the dryer duct, like you suspect. When I upgrade to click-free Panaflo's, I'll have to get some straight-tube ducting as well. Thanks for the wake-up call, pangit!

No worries Sometimes, I love the whole idea of using home made solutions and a bit of ingenuity too (usually other people's great ideas on these forums)! Rusty mentioned in another post about using Pringles tubes for ducting, as they are exactly 80mm in diameter. Either that or an empty coke bottle (not sure which size, I guess I'll have to take a ruler to the supermarket )

I'll probably do some experiments to test which one resonates the least, the Pringles or the Coke bottle.

Great, I think I've got some eating and drinking to do! But all in the cause of scientific research

Glad you like the green case too - it's not perfect, but I definitely prefer it to the yukky beige it used to be!

actually pringles cans (in Iceland at least) are 70mm not 80 mm

but that is quite good for me since my HSF is 70 mm

well if a pringles can works you better clean it really well.

i suppose it would also slightly damepn the sound?

while a coke can would amplify it.

I've added a few new photos with my latest mods, particularly showing a cheap way to decouple fans using silicone sealant.