Hi. Suppose I build a water cooling system, with the pump and radiator positioned in a remote location. Will it be silent, or does the water flow itself create noise? Thanks.

Not to be a salesman of it, but the Water Wetter by Redline actually stops splashing and makes the water one flowing object. So adding that might help any system. It also lubricates the pump and my pump has been basically noiseless for 3 years.

If you have pump in a remote location, there shouldnt be any noise. I could only see some noise from a super strong flow rate which could vibrate the pipes back and forth and make a hum or some other sound. I doubt you are doing it that strong though?

Yes, I too have a plan for my new place to make a water cooling system that has super long, like 20 foot pipes leading in and out. On the pipes will be fins like a baseboard heater. At the end of the fins will be a small radiator. I would expect much of the heat to be released by the time it hit the radiator. The pump and radiator would be next to eachother and in a closet or another room or something just away from the chair I sit in.

It's gonna be tough to build a system that is completely silent.

You can replace the cpu fan and gpu fan with a waterblock. No problems there.

But now you have 2 problems left.

1) The PSU.
What are you gonna do ? Most PSUs have a fan. And that fan makes a little noise. (All fans make noise, no matter what).

So I bought a watercooled PSU. Works very nicely. In fact, the PSU almost does not generate any heat. For a short while (about 2 weeks), when I had just bought a new cpu and gpu, the PSU was the only part in my PC being watercooled. The heat of the cooling system hardly went higher than room temperature.

There is only 1 problem with PSUs. Even without fans, they can make noise. My PSU is emitting some weird high-pitched sound. Not so loud, but because it is so high pitched, you hear it above everything. I've read a bit on the net (and on this website). And supposedly it's the coils inside the PSU. And there is no way to repair/fix that. I paid 200 euros for that PSU a few years back. I don't know when it started to make the noise. The prices have gone up to 250 euros now (280 import in my country even). I'm not gonna pay that for a new PSU every 2-3 years.

2) Airflow through the box.
I've had my PC without any airflow. When I had just bought the watercooled PSU, I had an AMD3400+ and a Radeon9700Pro. Both watercooled. No fans. No airflow. Worked fine for over a year. Then the memory on the R9700Pro melted. The R9700Pro waterblock only covered the gpu, not the memory chips. Modern gpu waterblock cover a lot more than the gpu itself nowadays.

Early this year I upgraded components again. Got a E8500 and a 8800GTX. Both watercooled (with the PSU). No airflow through the box. I kept an eye on temperatures. My hdd went 51C often. My case would heat up. The 8800GTX is known to run very hot. But without airflow, stuff is gonna get hot no matter what.

In the end I activated a casefan. Downvolted it from 12V to 5V. Spins nicely, almost no sound. But the minimal airflow through the case gives lower temperatures for my hdd and other components. At least 10C lower.

My only problem atm: the high pitch in the PSU.
I need to replace it.
I plan to buy a PSU with fan, which also brings a little airflow through the case. I don't need much airflow, just a little. If the PSU causes a little airflow, then I can disable the case fan again. Therefor I'd like to get a PSU with a fan where I can lower the speed. Either with a switch on the PSU, or by downvolting the power going to the fan. Anyone who knows such a PSU ? I don't want it to be done via drivers and software, because I use my system with Linux too.

About the sound of water flowing through the tubes ? I've never heard that. The hdd will be louder. Probably even when it is idle.

I was asking specifically about noise from the water cooling itself.

True, all fans make noise, but if it's a good fan running at low speed this noise will be below a human's hearing threshold.

I'm pretty sure all PSUs have coil whine (perhaps some more so than others), and I don't think it's related to its age. Personally I am using a Corsair HX620W, and I cannot hear its fan when idling (I haven't tested it under load). I can only hear its coil whine if I put my ear directly against it. You may want to consider getting it or the HX520W (I could tell you about all of their other advantages, such as having modular cables, or you can read the SPCR review).

Getting some minimal airflow with silent fans is pretty easy, and if one really water-cools everything even that much isn't necessary.

The hard drives will probably be the acoustic bottleneck. I hope a combination of an SSD and a 5400RPM drive will do the trick.

something like a Zalman water system (besides the noisy XT version) would be 1/8th as loud as a Corsair 620 at idle. that fan is not silent, it is quiet. So, the water system you choose should be drastically more quiet than what you expect, I am guessing.

It is my impression that Zalman's water systems don't offer enough of an advantage (compared to silent air cooling) to justify the expense and the trouble. If I do ever switch to water, I prefer to leave the possibility of high performance without risk of excessive noise.

They do justify the expense and the trouble, at least for me.
The fan on an 8800 might be unintrusive to some but it was annoying me... Waterccoling the video card solved the problem (CPU is still air cooled).