Question Noctua Fan very loud when used on a hyper 212 evo

[jack.h.tierney]

So I have a hyper 212 evo cooler on an i5-4670k. I decided to swap out the stock fan with a Noctua NF-12. I know the fan works fine cause I was using it as a case fan before. However now that I have it on the cooler, every twenty minutes or so it starts spinning at max speed and is very loud. I am not sure why this is or if it's something I can fix. I could always go back to the stock cooler since that worked no problem, but still, it's strange. My motherboard is a Q87m-e/csm if that matters.

 

[Bearmann]

Can you get into the UEFI and check the CPU fan controls? (Delete or F2 on start up)

 

[Karadjgne]

Check your temps on cpu. You didn't by any chance use Arctic silver 5 on the cpu cooler the last time it was repasted?

 

[jack.h.tierney]

I did actually. What's wrong with that?

 

[Karadjgne]

Ah. Arctic silver 5 is a heat cycle paste. It cures hard (dries out) after @ 200 heat cycles. (that's cold boots to stress test/heavy gaming heat and back to idle/off). This isn't a bad thing. Pastes don't actually transfer heat, it's all the silicates, minerals, diamond dust and other substrates that do. So when AS5 cures, it still works the exact same way it always did. Until you break that seal. This happens with hard shocks, vibrations, slight twists or movement of the heatsink. If you imagine AS5 is kinda like a weak glue, all is good until you break the seal, and then it'll never stick back again.

I'm betting when you changed the fan, a slight movement shifted the heatsink, broke the seal and the cpu is slowly heating up until it reaches @ 70°C, at which point the bios/fan software kicks the fan to max. It stays that way for a few seconds, cools off the cpu, rinse and repeat.

Repaste.

 

[boju]

S5 is ok but can do better. noctua nt-h1 has no cure time.

 

[jack.h.tierney]

I will repaste like you suggested but im not sure if that's the issue. Because I was monitoring temps with HWMonitor and the fans start speeding up even though the cpu is only at like 36 celcius.

 

[Karadjgne]

Is that the single temp for the entire cpu, or the hottest of every core? You could quite easily have 2 cores in mid-high 30's and 2 cores in 70+. If you go into bios, which is a moderate load, you should see the temp every core is at in that state. You should be somewhere in the 40-50°C range at worst after a few minutes.

Thr cpu fan is controlled by the cpu temp, unless there's malware or a background app putting cyclic periodic heavy stress on the cpu, temps shouldn't make a Noctua hit max rpm noise. The NF-F12 is almost silent upto @ 700rpm and only starts getting louder after that.

Bios fan curves don't work by rpm on the fan, they work by duty-cycle to temp curve. At x°C it'll run at 30% duty-cycle (1200rpm fan = 400rpm) and will slowly climb until it reaches 70°C and 100% duty cycle (bios default) (1200rpm fan = 1200rpm). So something is registering some seriously high temps somewhere, for some reason.