PWM fans RPM

Casterina · 26 Jun 2016 at 12:45

I'm using the Akasa Apache PWM fans (600-1300RPM) for heatsink and case with Standard fan profile set in the BIOS, it currently runs at around 900RPM during idle and was wondering is the RPM a little high for idle and should I change it to around 700RPM?

Also is setting the fan speed to 100% once the temps is above 55-60C too aggressive? As I would like to keep the CPU (6700k @ 4.7GHz) and GPU (Sapphire R9 290 Tri-X) temps below 70C when gaming.

I know this is user preferences but wanting your opinions on it.

HACO · 26 Jun 2016 at 12:55

As someone who runs fans at 300rpm I have to say that 900 is super high for me. The profile you're using is so aggressive.

I'd set them to zero until 50 degrees, then to 25 until 60, then to 50 until 75, and 100 only after the 85 degree mark. Maybe even after 95.

BluD · 26 Jun 2016 at 18:22

Yeah 900 is a bit loud for idle, i have most of mine off like HACO at idle, just one 140mm case fan behind the CPU running at 300rpm. The rest i would set up to the temps HACO mentions above depending on your fans, if your fans dont push as much air as HACO's you might need to set it a little more aggressive.

doyll · 27 Jun 2016 at 09:07

I set idle speed for case and cooler to as low as possible with all components staying below cool-ish. By other components I mean motherboard components and things like HDD.
Maximum heat to rpm is set at 65-80c depending on components involved. My systems never run about 65c, .. rarely above 55-60c. Maximum speed setting depends on how many setting can be made in temp to speed curve to give me acceptable sound levels and temperatures in normal use, not at maximum load .. because the never or rarely run at 100% load.

Casterina · 28 Jun 2016 at 20:15

My motherboard (Asus Maximus VIII Gene) doesn't let me go below 20% speed which at 20% it runs at around 900RPM.

JR23 · 28 Jun 2016 at 20:53

Does it yield better results if you use the header in DC mode rather than PWM?

JR

doyll · 28 Jun 2016 at 20:57

20% PWM of a fan that is 1300rpm at full speed is 260rpm. Many fan PWM circuits have a minimum rpm of like 45%, which is 600rpm .. about what your fans' idle speed. No idea exactly why your fans are not idling down slower though, sorry.

Bone9 · 28 Jun 2016 at 21:09

Casterina said:
I'm using the Akasa Apache PWM fans (600-1300RPM) for heatsink and case with Standard fan profile set in the BIOS, it currently runs at around 900RPM during idle and was wondering is the RPM a little high for idle and should I change it to around 700RPM?

Also is setting the fan speed to 100% once the temps is above 55-60C too aggressive? As I would like to keep the CPU (6700k @ 4.7GHz) and GPU (Sapphire R9 290 Tri-X) temps below 70C when gaming.

I know this is user preferences but wanting your opinions on it.

My Akasa Apache cpu rad fan runs at 607rpm at idle.

Stealthploit · 28 Jun 2016 at 23:24

i would setup custom profile for the fans 900 is a bit slow for me for idle but its hot here

doyll · 29 Jun 2016 at 08:07

Stealthploit said:
i would setup custom profile for the fans 900 is a bit slow for me for idle but its hot here

900rpm is well above normal idle speed. Either your case is not flowing air like it should or it is way more than 'it's hot here'.

Bone9 · 29 Jun 2016 at 09:03

Can you guys give me a quick guide on what you set your fan profiles upto please?

All off at idle? (Including the rad fans)

Do you set up the rad fans to the same profile as the case fans?

If off at idle at what temp do they start to spin and at what temp are they at your max rpm? Do you set the max temp so the fans are at full speed or a lower percentage?

Also what are you idle and max temp for you cpu and case at load and at idle?

That's it,

Thank you.

doyll · 29 Jun 2016 at 10:11

My fans always run, but sometimes that may only be 300rpm.

I set case fans to flow same mount of air as radiator fans.

Idling at 300rpm they make so little noise (about half of what room ambient is) they can't be heard anyway .. maybe if an ear was so close it was in danger of being hit by the fan they could be heard.

Temps very between systems, but usually idle is is low it mid 20s and full load is 50-60c. But only one of my systems is wet. All others are dry (air).

Casterina · 29 Jun 2016 at 15:01

JR23 said:
Does it yield better results if you use the header in DC mode rather than PWM?

I have switched from PWM to DC mode in the BIOS and the fans now idle at around 280RPM except from CHA3 fan which I assume is the PWM splitter that I'm using is getting direct power from PSU via molex? If so, could I get a 1 to 3 PWM splitter which powers via the motherboard fan header?

This is the Standard DC mode fan profile I'm using at the moment, is the profile good for case and heatsink airflow?

Bone9 · 29 Jun 2016 at 21:27

doyll said:
My fans always run, but sometimes that may only be 300rpm.

I set case fans to flow same mount of air as radiator fans.

Idling at 300rpm they make so little noise (about half of what room ambient is) they can't be heard anyway .. maybe if an ear was so close it was in danger of being hit by the fan they could be heard.

Temps very between systems, but usually idle is is low it mid 20s and full load is 50-60c. But only one of my systems is wet. All others are dry (air).

Cheers for that. What are your system temps?

doyll · 30 Jun 2016 at 09:30

Bone9 said:
Cheers for that. What are your system temps?

Sorry, but either you didn't read the last line of my post you quoted, or I don't understand your question.

Bone9 · 30 Jun 2016 at 09:47

doyll said:
Sorry, but either you didn't read the last line of my post you quoted, or I don't understand your question.

I did. I assumed you were talking about cpu temp and not system.

My cpu idle is 24-27 and 50-60 gaming. My system temp is 30 idle and 43 gaming.

doyll · 30 Jun 2016 at 10:28

Bone9 said:
I did. I assumed you were talking about cpu temp and not system.

My cpu idle is 24-27 and 50-60 gaming. My system temp is 30 idle and 43 gaming.

Got it! I don't pay attention to sysstem temp. I tend to look at individual components. like SSD, HDD, mobo, GPU, RAM, etc. These vary depending on system and clocks, but are all within the CPU min/max range. 6700K are almost identical, but 1366 systems run much higher NB temps if not cooled properly. For example, my 1366 systems all have idle speeds of 500-600rpm because if airflow is lower over motherboard idle temps of motherboard run higher than when system is under load and fans speed up.

Hope that makes sense.

Bone9 · 30 Jun 2016 at 12:55

Ah OK so it's best to check out what my components temp range is and adjust my case fans to them. Cheers.

Casterina · 30 Jun 2016 at 13:30

Can I power 3 PWM fans using a splitter without power from PSU but only with the fan header on the MB?

doyll · 30 Jun 2016 at 13:36

That is kinda like asking, "Can I drink of these containers full of water?" We have no idea what the power requirements of the 3 fans are, therefor cannot give you an accurate answer. Motherboard fan headers are usually rated up to 1a / 12a load. Fans use much more power at startup than when running, so I would not load a fan header with more than about 0.7a / 8w of load. If your 3x fans have a combined total wattage of below 8w then yes you can run all three from motherboard fan header.