Originally Posted by Art Vanelay
Scythe AP-15s are good,
It's not just the noise level, it's also about how they sound, and I can't stand those fans, personally.
I kept a noctua SP in my son's case as the exhaust fan. They are about the same as they Yate loons I also have in his case, I just have yet to see or hear anything special about them myself. The SP was one that had harmonics issues on a radiator, but it works ok as a case fan. I do like the accessories like the little resistors and rubber mounts etc. I just don't see any performance difference over a $7 yate loon.
True that some GT samples have been wonky and their lack of air noise and ball bearing do create a little different tone. I just have had anything come close in low noise level.
Also I noticed just the other week that GTs for whatever reason do not like PWM base fan controllers. It has to be pure analog voltage (resistance based) or they can have a whine. My sunbeam rheosmart works well in manual mode (analog), but my crystalfontz (pwm based) does not do well with them.
Gotta have the right analog fan control for GT 15s.
I have also seen them have certain RPMs where they spike in harmonics. I have measured up to 5 harmonic bumps throughout the speed range. So definately not the best fan to ramp up and down through the range of speeds, you have to pick a goot spot and stick with it. At 1800rpm though, they have an untouched noise/cfm ratio. At 1800 they are producing a PQ hump that matches most fans when turning 2200rpm and they do it at several dbA quieter than anything else. Still don't know how they do so much better than the others.
The Helix fans are also good and have a similar noise level per RPM as the GT. They don't have the same hump in the PQ curve though so 1800 is like most 1800rpm fans. Helix advantage is their better looks, cheaper price, no harmonics issues, and no ball bearing noise at slow speeds. They are a good opion too, but not quite up to GT levels. GTs are special in regard to noise and strong PQ curve.
I'm hoping the Helix V2 comes out some day that puts the GT in it's place. Haven't tried cougars yet.
GT AP-29s are another to consider for thr h100i if you wanted to retain super high speed performance and PWM. They don't come wired with all four wires, but reported the circuitry is there and just takes some soldering.