Question CPU Fan Spinning Up Super High

[Draxonn]

AMD X4 860K
ASRock FM2A88x Pro3+
Fractal Design Focus G Case

I recently put my computer into a new, high airflow case (along with new SSD) to hopefully quiet it down. However, now I'm noticing my (stock) CPU fan spinning up to 45K or higher when I game, even though temps are staying low (53-55). If it did this before I didn't hear it. I've been unable to limit this behaviour with BIOS settings.

I use ATuning to monitor fan speeds and temp and turn down the CPU fan on the fly. However, it's FanTastic function measures different fan max speeds at different times. Usually, its at 35k max, which keeps fan speeds down. During gaming, Max jumps to 65K which means the same fan % is at least 1.5 times higher RPM.

I'm thinking about getting a new cooler, but if I can't control the fan speed a bit more, I'm not sure it will make that much difference. It's just really loud and the extra RPM seem completely unnecessary for cooling, by any metric I can find. When I lower the fan speed significantly, it doesn't impact the temps in any way that I can see.

 

[Barty1884]

The stock fan is quite load. Honestly, a replacement cooler likely would've been a better route before going to a new case.

Doesn't sound like the software is capturing 'max' though, only current.

Almost any halfdecent aftermarket cooler will be quieter than the stock cooler, even if you couldn't control it! Provided you have a 4Pin PWN fan to connect to the CPU_fan header, you'll be able to control

 

[Draxonn]

Thanks for the response.

The stock fan is quite load. Honestly, a replacement cooler likely would've been a better route before going to a new case.

To clarify, the case was a definite improvement. I now get more airflow (and cooler temps) from a single 120mm fan than I used to with 4 80mm fans (which were far noisier).

I've poked around in my BIOS some and it seems the BIOS is somehow hardcapping the fan speed. A-Tuning will test a fan from 10%-100% to find RPM readings. Usually, the hardcap is at 3500RPM. However, sometimes, for some reason, the hardcap will unlock to 6500RPM--generally when the CPU is under load. Right now, it's hardcapped at 3500RPM again, but I don't know why. I reloaded a BIOS save state which seems to have changed something, but I can't figure out what option it would be. (Interestingly, I've been having problems with CHA_FAN3 not picking up. While the CPU fan is hardcapped lower, that fan is working up again--even though I have to manually activate it in BIOS by simply adjusting its settings). Not impressed with my MOBO right now.

 

[Draxonn]

The stock fan is quite load. Honestly, a replacement cooler likely would've been a better route before going to a new case.

Doesn't sound like the software is capturing 'max' though, only current.

Almost any halfdecent aftermarket cooler will be quieter than the stock cooler, even if you couldn't control it! Provided you have a 4Pin PWN fan to connect to the CPU_fan header, you'll be able to control

Sorry to bother you again, but I'm still looking for help with this. The issue is that my CPU fan is behaving entirely inconsistently. Sometimes while gaming it will sit at 3000RPM, sometimes it will sit at 4500RPM. The game is the same, the ambient temps the same, the CPU temp the same. This seems to be a software setting somewhere (perhaps in BIOS), but I can't figure it out. It's like the computer is applying two different Fan curves randomly. It seems to change between bootups, so I suspect something in the BIOS, but I don't know what. The BIOS generally stays the same.