I have a NZXT H400 case which came with 3 non-PWM fans. PWM (Pulse Width Modulation) or modulation with the width of an impulse, is a widespread term in the world of electrical engineering. The Pure Wings 2 non-PWM fans have 3-pin cable having a length of 450mm. But you can only monitor one of the devices attached to it. Dear all, I would like to know if a fan splitter cable would be a possible outcome for my specific problem. At this price point, it’s a smart buy. Even with BlinkWithoutDelay style code once you start adding other code it becomes more difficult to achieve a reasonably fast PWM frequency. What I don't understand is - I've seen online that non-PWM fans only run at one speed while PWM fans have variable speed based on the heat. The weight of the non-PWM 120mm fan with the box is 0.130kg. I got 4 fans to set up, they are all non PWM types, one of them is supposed to fit behind a CPU watercooling radiator, the others stand alone inside the case. There are PWM splitters which take the burden of DC power off the motherboard while providing total thermal control. So yeah, I am going to get a couple Corsair SP120 fans but Im not sure whether to get the PWM version or the non-PWM version. Thanks to the rifle bearings, the MTTF of these fans is rated at 80,000 hours at 25°C. Oh I guess I strayed from my point, but it was if you have a fan controller it doesn't matter if you get PWM vs. non PWM, but rather the airflow, static pressure and noise which becomes the deciding factor. The weight of the non-PWM 140mm fan with the box is 0.158kg. The third type of fans that use four wires are PWM fans and that is what will be discussed in this article, along with PWM pumps. My original question perhaps could be rephrased as, what really is the difference between non-PWM pins and PWM pins if they are both capable of 490Hz write frequency? Otherwise, this fan’s specs – especially airflow and noise – are typical for a non-PWM fan in this size range, and that’s not faint praise. These fans will be for my H100, the stock fans are absolute trash, they sound like a leaf blower. FrozenCPU.com breakdown of differences between pwm computer fans and 3 pin computer fans. I finally found out the difference between PWM fans, and non PWM and now im looking at controllers. Hi guys, ok so im kind of new to the whole PC fan thing, and im looking to add about 3 extra fans to my case. The Swiftech 8W-PWM-SPL units ($10) will control eight PWM fans with the signal from the CPU_FAN header (or any PWM plug that allows for thermal control). A 3-wire fan can be controlled using the same kind of drive as for 2-wire fans—variable dc or low-frequency PWM. I am able to set up a fan curve in the MSI bios, so when it gets hot in the case, the fans speed up, and vice versa. 3. The tach signal indicates whether the fan … The difference between 2-wire fans and 3-wire fans is the availability of feedback from the fan for closed-loop speed control. There are 2 that i like the look of that are recomended by most people. And if I'm not mistaken, the Define R4 has an in-built fan controller which you can use if you want to change the speed of the fan yourself. These fans are using Rifle bearings with 4-pole motor. Thanks in advance.