Question FAN speed control only works at BIOS

Myronazz

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Sep 5, 2016
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Hello,

I upgraded a system from an i3 4170 to i5 4440. Long story short, the i3 stock cooler wasn't enough to cool the i5, so I got an Arctic Alpine 12 95W cooler, installed it along with brand new MX-4 thermal paste and... the temperatures were WORSE.

I noticed that the fan was really quiet, and at first I said: "Wow they weren't kidding about it being quiet." But then I looked at temperatures exceeding 100 degrees, so I forced restarted the computer into BIOS to see maybe if I have screwed up something, and as soon as I went there, the fan speed turned really loud until the CPU temperature got back down to 30 degrees. Everything made so much sense, because the fan sounded like a 95W TDP one.

So... that means, for whatever reason, Windows cannot control the fan but the BIOS can. HWMonitor reports a speed of 1700 RPM, but I doubt that because the fan is far too quiet.

I already reset the BIOS settings by removing the CMOS battery, and also tried to reset to optimised defaults. Nothing really works, the fan is always at low RPM in Windows.

Any ideas?
 

Myronazz

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Sep 5, 2016
325
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Update: I bridged the SENSE and CONTROL pins, leaving only the voltage pins but the fan is still not spinning at full speed. It can't be broken, can it? It does work in BIOS

Update 2: The fan may actually be broken. I installed it on an older machine I have that has a calibration smart fan feature, and it spins so low you can actually see the blades. For comparison, I used a stock cooler, and at the same point in the calibration process, it was spinning fast. So I am thinking... maybe the fan is internally broken with a bad threshold or something along those lines
I recorded this in a video here

Update 3:
I installed the cooler on yet another machine (i3 6100u) and it seems that motherboard can control the speed better. But the thermals are dissapointing: 68 degrees max and 65 degrees average with a stress test. A 95W TDP rated fan should cool an i3 better than this. Either it's a faulty fan or Arctic is pulling some bogus numbers.
 
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