I built a new HTPC from mostly spare parts. It's running a Phenom II X4 with the stock cooler. When I put it together in an old Lenovo case, it was almost silent sitting on the floor under the TV. I recently splurged on a Lian Li PC-C50 case, and with the same setup it sounded like fighter jets in the living room. The new case was easily 10 times louder, including the two 120mm fans it comes with.
I've dropped the voltage to the 120mm case fans down to 7v (by switching molex pins), and that makes them tolerable but I would still like them to be a little quieter. I was going to get a fan controller, but I see that most of them will only reduce to 6 volts. Would I be just as well served to change the connectors up for 5 volts and consider that as quiet/slow as those particular fans will ever get?
I'm going to HAVE to replace the CPU cooler to quiet it down. I don't have a budget, but cheaper is always better. I've been looking at the Noctua NH-D14, but I don't think it will fit my case due to height. Case is about 6" outside dimension so probably only 5" inside on top of CPU. Can anyone recommend a virtually silent CPU cooler that would fit that case? I've read plenty of reviews and tests, but I'd like some real world feedback. Reviews said the 120mm fans in the Lian Li were quiet, too.
Other stuff worth mentioning - CPU and case temps are not a problem at all. With just the stock cooler running at 1300 RPM, the temps stay well within acceptable range even under load. Everything's running on an ASRock 960GM/U3S3 FX, and I've used the BIOS to slow the CPU fan down as much as possible without overheating. Also, Speedfan can't control the 3pin case fans.
I have X4 840 as HTPC with Freezer 13 Pro and 120mm Fractic fans for intake/exhaust and it is whisper quiet. Freezer is @ 700rpm and fans @ 800rpm controlled by MBD BIOS and all this in an old NZXT case.
I have the same problem with that cooler as the Noctua. Specs for the case are max cooler height of 135mm, and I think that is still pushing it. Both Noctua and Freezer 13 Pro show 160mm for height.
I did drop power to the 120mm fans down to 5 volts, and I think I'll leave them alone unless the new cooler makes them seem loud again. Speedfan won't tell me how fast they're spinning, but it's pretty slow. Temps only increased 4ºC at the lower speed, and I should get that back with a better CPU cooler.
Fluid dynamic or hydro bearings are the best for quiet fans. You will notice the difference. I swapped all my case fans out recently with Logisys brand 92mm and 120mm fans (4 of them) and it is very quiet, with better temps as well. That brand is usually half the price of the name brand fans, for the same quality and silence.