Asus mobo, fans spinning up on high cpu usage!

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sleepysonic
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Asus mobo, fans spinning up on high cpu usage!

Post by sleepysonic » Sun Jul 27, 2014 10:18 am

I'm using q-fan at the moment.

I have my front 20cm fan on my cpu header, my back noctua fan on chassis fan 1, and my dual noctua d-14 cpu fans on my chassis fan 2.

In q-fan I have it set so the "chassis" fans only spin up when cpu reaches 57C. So far it seems if I don't use the computer these fans do stay turned off.

BUT, as soon as I run prime95, my fans spin up for 3 seconds, and then turn off for 3 seconds, and repeat! My cpu temperature is <40C and happens at even 35C. It seems to be revving the fans up because of my high cpu usage. Is this a common practice? Is there a way to stop this?

This is almost more annoying than just having the fans always on because now I can hear them constantly changing.

Speedfan shows incorrect temperatures and no fans to control.

I just want my fans to work when the cpu gets hot, not when the cpu gets busy :(. Any help and advice?

edit: z97m-plus with i7 4790k

edit2: Okay, I've resigned to the fact that there must be some kind of hard-coded fan control which turns the fans up when cpu usage is high. This is quite a shame as otherwise I could potentially have a completely passively cooled system for general use. I'm just going to keep the fans on low constantly.

Krydel
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Joined: Thu Jul 24, 2014 9:53 pm

Re: Asus mobo, fans spinning up on high cpu usage!

Post by Krydel » Sun Jul 27, 2014 12:55 pm

Why are your CPU fans not plugged into your cpu header and your 200mm not in a system fan header? Switch them around and see what happens; is the 200mm even PWM to be controlled properly by the CPU header?
Last edited by Krydel on Mon Jul 28, 2014 5:49 am, edited 1 time in total.

Abula
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Re: Asus mobo, fans spinning up on high cpu usage!

Post by Abula » Sun Jul 27, 2014 9:36 pm

sleepysonic wrote:I'm using q-fan at the moment.
BIOS?
sleepysonic wrote:I have my front 20cm fan on my cpu header, my back noctua fan on chassis fan 1, and my dual noctua d-14 cpu fans on my chassis fan 2.
Why do you have the CPU fans on the CHA_FAN headers? Did you change the Q-FAN on the CPU_FAN from AUTO to ADVANCED?
sleepysonic wrote:BUT, as soon as I run prime95, my fans spin up for 3 seconds, and then turn off for 3 seconds, and repeat! My cpu temperature is <40C and happens at even 35C. It seems to be revving the fans up because of my high cpu usage. Is this a common practice? Is there a way to stop this?
Some fans dont like certain voltages and in some cases they need higher voltage to start then to keep spinning. Install AI Suite and enter FanXpert2 (or 3 not sure what version it will come with), and try to run the tunning, it will determine the minimum and maximum rpms for each fan, will also determine the minimum rpm to keep it running, etc.
sleepysonic wrote:This is almost more annoying than just having the fans always on because now I can hear them constantly changing.
On fanXpert you can set your own graph for rpms based on the temperature, once you establish the minimums you can try doing below the graph before certain temperature with a big jump toward covering the minimum spinnng that way they should spin once the temp is reached.
sleepysonic wrote:I just want my fans to work when the cpu gets hot, not when the cpu gets busy :(. Any help and advice?

edit: z97m-plus with i7 4790k
Btw return the CPU fans to the CPU_FAN header, the chasis fans have much higher restriction on bios than the cpu_fan (at least on Z87, not sure on Z97), but if you run fanXpert all bios restrictions should be removed and they should drop as low as the fan was design or at least how FanXpert recognizes them. Depending on the fans that came with the D14 (the 2011 version has pwm fans the before has 3pin fans), you should change in the bios the Q-FAN from AUTO to ADVANCED to run the 3pin fans on the CPU_FAN header.
sleepysonic wrote:edit2: Okay, I've resigned to the fact that there must be some kind of hard-coded fan control which turns the fans up when cpu usage is high. This is quite a shame as otherwise I could potentially have a completely passively cooled system for general use. I'm just going to keep the fans on low constantly.
Btw i wouldnt run the 4970K fanless, mine can spike in second to 50C just simply webrowsing, this is with fans spinning at 500rpms, but without i bet i can pass 60 super easily. Give a shot to FanXpert, you might be able to still do what you want.

sleepysonic
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Joined: Wed Jul 23, 2014 3:44 am

Re: Asus mobo, fans spinning up on high cpu usage!

Post by sleepysonic » Sun Aug 03, 2014 10:44 pm

I want the CPU fans to turn off entirely until the cpu gets warm enough to need it. These are 3-pin fans

I want the back chassis fan to turn off entirely until the system needs it. This is a 4-pin fan.

The front 20cm 500rpm can stay on but I would rather it turn off too. This is a 3pin fan.

Issues:

I have the 20cm fan on the CPU header because it appears any fan on that header is not given the option in q-fan or xpert fan to have the fan turn off entirely. I want the cpu fans to turn off more than anything as they are the loudest and aren't PWM so the lowest it can go is "60%" in DC mode.

There is no "auto" or "advanced" q-fan mode in the bios that I can see. I see all the graphs and I am using manual mode with the 'fan off' ticked. I now have it set that the fans shouldnt come on until the maximum temperature it allows, but it made no difference.

Even though both applications claim they will keep the fans OFF until a specified temperature, that does nothing to stop this. They also ignore all spin-up and spin-down parameters set in xpert fan and turn on and off instantly.

Here is what is happening, as soon as I use a stress test (so either HIGH core cpu temperature, or high cpu usage) both the fans that were OFF are turned on and sped up to 100%. Sometimes it turns on and off twice within 2 seconds as it is quickly changing whether to keep the fans on or off.

There appears to be some kind of hard-coded invisible setting inside the bios that says "If core cpu temperature is greater than 75C and a fan is off, then turn that fan onto 100% until core cpu temperature is less than 75C". I'm not sure if it's 75C exactly or not but it seems around that.
It does this even if the CPU temperature (which is what the fans are meant to be looking at) is 45C or less.

I'm fine with them turning on for that, I have adaptors to turn the 100% fan speeds down to something not so loud. But the problem is it spins up immediately and spins down immediately with no way to change. So if the temperature goes from 75 to 74 to 75 to 74 those fans are turning on and off and on and off which can't be good for the fans.

Speedfan shows no fans to control whatsoever. Is there a way to get speedfan to see them or is it just a matter of incompatibility?

lodestar
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Re: Asus mobo, fans spinning up on high cpu usage!

Post by lodestar » Mon Aug 04, 2014 5:27 am

sleepysonic wrote:...Speedfan shows no fans to control whatsoever. Is there a way to get speedfan to see them or is it just a matter of incompatibility?
The current version of SpeedFan does not work with Windows 8.1 64 bit, showing no fans. There are reports that although it works with Windows 7 and 8 odd effects are being observed with Asus H97 and Z97 boards such as clearly inaccurate temperature sensor readings. So SpeedFan is not likely to be of help here.

The DH14 is a fine cooler but there is not much that can be done with the two 3 pin fans it came with if idle speeds of around 700 rpm at 7V are too noisy by your standards. In this situation the best thing to do will be to replace those fans with one or two PWM fans, one could be enough if you choose something like the Noctua NF-A15 140mm PWM. There is a practical issue with the NF-A15 because it won't fit with the standard D14 fan clips but Noctua support will send you the right clips if you email them. With a NF-A15 using just the BIOS Silent mode you should see idle speeds in the 300 to 400 rpm range at idle, dependent on ambient temperatures. If you just wanted to use the BIOS mode the best way to deploy your existing 4 pin Noctua would be to use the PWM Y cable that either it or the A15 is supplied with, and run both from the CPU PWM header. This combination of exhaust and CPU PWM fans running at the low speeds that the BIOS Silent mode allows would probably be enough for most people. It might be worth trying the BIOS fan tuning which the Asus H97 boards have to see if that helps reduce fan speeds. Alternatively if as suggested by Abula you run Fan Xpert 2+ then you could probably get the Noctua fans to run somewhat slower than the 300 to 400 speed range, possibly more like 200 to 300. I am not convinced that the fans would actually be audible in a case at these speeds.

Going this route would give two potential options for the front 200mm fan. The first would be to use either the BIOS fan tuning or Fan Xpert 2+ to see how low a speed you could get it down to. The second would be to use the Allow Fan Stop feature of the H97M-Plus BIOS to keep this fan turned off until a set chassis temperature is reached. By default this is 40C, it can I think be set higher, so in practice the 200mm would only turn on and run under high system stress and/or high ambient temperature conditions.

The advantage of using PWM fans in the way suggested here is that particularly with Fan Xpert 2+ tuning idle speeds would be so low as to be effectively silent. Equally the PWM fans will speed up under high system load situations to give increased case airflow to hold CPU and system temperatures in check. In practice a balancing point will be reached. There is a facility in both the BIOS and Fan Xpert 2+ to change the default PWM fan profiles so you can influence how the fans work. But the aim is of course not to get too near to the 75C CPU or chassis temperature trigger points where fans go to 100% duty cycle.

Abula
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Re: Asus mobo, fans spinning up on high cpu usage!

Post by Abula » Wed Aug 06, 2014 9:45 pm

I personally haven't experience anything like what you are describing with my Asus Maximus VI Gene, not sure if the motherboard is defective or maybe there are different version that dont allow what i can do with mine. In my setup, fanXpert2 can override bios restrictions, fan can go extremely low, much lower than 60%, for example here is an Antec True Quiet 140 ran on CHA_FAN2 header,

Image

Now as you can see the fan is idling around 200rpms, this is less than 30% on the table, and its stable, even if the bios doesnt allow this setting FanXpert2 overrides it, im not 100% sure this is how all asus motherboards work, but i would assume most should, unless Asus purposely crippled certain motheboards.

Now the Q-Fan from Advanced to Auto, has been on the Asus Maximus series in all their line from Sandy to Ivy to haswell (not sure about devils canon), not sure if all asus motherboards has it, but was one of the nice feature that only Asus had.

Now what i would do is use the 4pin you have on the CPU_FAN, seems all your other fans are 3pin, if so, connect them to CHA_FAN headers, and re run fanXpert2 or 3, see what are your graphs, and second try to move the dot below the limit line, that's how i remember someone else posted was able to turn off fans, this is something i never tried nor i care about it, running my fans to inaudible levels is good enough for me.

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