I'm a first-time PC builder, and I've been using the stock heatsink for a couple of months, and would love to get a heatsink that works well, and is extremely quiet. I'm looking to do some home recording, and would like the noise from the computer to not get picked up by condenser microphones.
I'm using a Coolermaster HF912 case, with an intel 5 2500k sandy bridge processor on an Asus P8Z68-V Pro MB. I'm not overclocking yet, but would still like it as an option for more processor heavy pro tools sessions.
Heatsinks don't make noise. Fans do. It sounds to me like the only thing that will satisfy you is to locate your tower as far from your work as possible as all fans make some noise. I suggest looking for long cables.
@ram1009: Doesn't the fan on the heatsink make noise? I definitely hear the sound coming from the stock heatsink.
He's simply being technical. The heatsink is the chunk of metal, which typically has a fan bolted to it. I haven't used a lot of noctua products, but I believe they focus on low noise cooling products. Coolermaster is pretty good as well.
I don't know if they still make passive heatsinks (no fan), but they did exist in the past, they were expensive and had very thin copper sheets which fanned out like pages of a book. Those may not be capable of keeping up with modern CPU's though.
Other potential sources of noise:
Mechanical HDDs (SSDs don't make noise)
You can run a Noctua NH-D14 in passive mode with no fans at all, you can also do the same with a Thermalright 120 Extreme, neither will give you high overclocking headroom like that, but passive is as quiet as you can get regarding the CPU cooler.
As a matter of fact the original Thermalright was released as a passive cooler option, but it's overclocking cooling capability started the quest for cooling supremacy with the cooler.
Leading to the Thermalright Ultra 120 Extreme, (TRUE)
actually I do agree, if you really don't like the noise you can always get a room and do get it customized to be sound proof, put your right there and somehow line your wires up so you can play outside that room, and voila, soundless system appears.