Just got a Antec p280 and was going for a silent build, but I notice the 3x120mm exhaust fans are making this subtle clicking noise.

Is this normal and how can I fix this?

If this isn't fixable, what replacement fans would be quieter without the clicking?

Didn't try stock P280 fans so do not know if it's normal or not.

Generally speaking every fan is going to make some kind of noise, some because of the way the bearing is designed, some because of manufacturing defects, for example the fan in my Corsair PSU chirps, annoying as hell and I can't replace it because it's inside the PSU.

There are a number of fans you could try. Nexus classic is a good choice, but the latest black and white frame nexus that I got is making a chirping noise about 50% of the time when mounted vertically and 100% of the time when mounted horizontally. Personally I've become a fan of Scythe FDB fans, they seem to have the most consistent quality and the bearing noise is almost non existent. They're relatively cheap too. If you do not like that option there are other options such as Scythe Gentle Typhoon, Noctua, or Noiseblocker, but those are more expensive. You might want to try pocking in the "fans" section of the forums for better luck.

Antec is sending me a replacement fan. But I have a feeling it might also do the clicking sound. Would love to have 3x Noctua but that would cost more than the case itself. My CPU Big Typhoon heatsink has a nice fan that I can't even hear it spin. Not sure what brand it is, but I heard they are yate loon fans.

Yate Loon and Nexus fans are almost the same thing. Nexus is just a customized 1000RPM version of Yate Loon. Report back when you get the fan, but I think it will also click.

Just tested out a Noctua NF-F12 PWM 120mm fan and I'm hooked. It is the quietest fan I've heard. Zero clicks or whine even for a PWM type generally known to have this issue. It was 2x as expensive, but worth it since I'm obsessed with silence. Came with sleeved y-splitter, extension and low-noise-adapter (i assume it just cuts the voltage with a resistor).

I gave in, just ordered 2 more. Now I can custom control the fan speed via my motherboard header instead of a switch in the back of the case.

The P280 stock fans are nice and quiet for most people, but I'm too nit picky with my ears. I'll report back when antec sends me the new replacement but probably it will click too.

Got the Antec replacement 120mm fan. As expected it also clicks subtly.

Well now what to do with 4x 120mm antec fan lol.

This! http://www.youtube.com/watch?v=VUbpb23yTK8

But you might be satisfied with running them in vertical orientation (4x of them in push/pull on the hard drive cage), undervolted to 5v? With the Noctua fans on the CPU heatsink or rear/top exhaust vents.

lol crazy video.

Well reason why I have 4x Antec fans because I didn't like their clicking noise and replaced them with noctua. I wouldn't wanted to put it back in my case. Maybe I can stack them and make a leaf blower.