CPU fan question

[EJ993]

Hi!

 

I have h80i gt cpu cooler, with 2 fans installed, one is af120 and other is stock sp fan which comes with cooler itself. I have set both fans to spin at 30% on idle when tems are low (around 37-42 degrees), so that I couldn't hear them. The story is that 2 days ago I installed gtx 980 gpu and started to notice that sp fans sometimes stops spinning, but not af fan. After some testing I realized that when tems are lower than 60 degrees then sp fan doesn't spin, but when they get higher then it immediatelly starts to spin. Then I checked my bios and saw than I have set that fans would start to spin at 50% speed after cpu reaches 60degrees (20% faster). After seeing got an idea that maybe fan just can't spin that slow (at 30%) when idle, even tho it spun perfectly before gnu installation. So I decided to change minimum fan speed to 40% and now it spins all the time, like it should. 

 

BTW I have tryied to replace sp fan, so its definitely not the fan problem.

 

So, should I worry about anything? Its just weird that for some reason it could spin at 30% and now it can't.

 

Thanks

[0ld_Chicken]

Hi!

 

I have h80i gt cpu cooler, with 2 fans installed, one is af120 and other is stock sp fan which comes with cooler itself. I have set both fans to spin at 30% on idle when tems are low (around 37-42 degrees), so that I couldn't hear them. The story is that 2 days ago I installed gtx 980 gpu and started to notice that sp fans sometimes stops spinning, but not af fan. After some testing I realized that when tems are lower than 60 degrees then sp fan doesn't spin, but when they get higher then it immediatelly starts to spin. Then I checked my bios and saw than I have set that fans would start to spin at 50% speed after cpu reaches 60degrees (20% faster). After seeing got an idea that maybe fan just can't spin that slow (at 30%) when idle, even tho it spun perfectly before gnu installation. So I decided to change minimum fan speed to 40% and now it spins all the time, like it should. 

 

BTW I have tryied to replace sp fan, so its definitely not the fan problem.

 

So, should I worry about anything? Its just weird that for some reason it could spin at 30% and now it can't.

 

Thanks

I wouldn't really worry about it although it could be due to voltage drop if you have an undersized or going bad psu.  could be that most fans will run at a lower speed like 30% (depends on the fan) if you are lowering the speed but not if they are starting (have to go to something higher like 40% then drop down) but you probably already knew that.  I think asus fan suite 3 does this, they call it something like "super oversilence" or something like that. 40% should be ok as long as they arent too loud

[EJ993]

I wouldn't really worry about it although it could be due to voltage drop if you have an undersized or going bad psu.  could be that most fans will run at a lower speed like 30% (depends on the fan) if you are lowering the speed but not if they are starting (have to go to something higher like 40% then drop down) but you probably already knew that.  I think asus fan suite 3 does this, they call it something like "super oversilence" or something like that. 40% should be ok as long as they arent too loud

I have ax760 psu, so more than enough power for 4770k and single 980. Anyways I'm going to replace that stock fan to quiet sp120 fan, Im just curious why did this happened. Or maybe something is wrong my system.

[0ld_Chicken]

I have ax760 psu, so more than enough power for 4770k and single 980. Anyways I'm going to replace that stock fan to quiet sp120 fan, Im just curious why did this happened. Or maybe something is wrong my system.

yeah that is plenty of power. I dunno, that is kinda strange if it worked before the new gpu.  can't do 35% in the bios?

[EJ993]

yeah that is plenty of power. I dunno, that is kinda strange if it worked before the new gpu.  can't do 35% in the bios?

haven't tried 35%. Anyways no reason to do that, because it can't spin at certain low speeds, which is the problem. But, yeah, 40% works perfectly.

[EJ993]

Also if it helps Im using asus maximus gene vii motherboard.

[EJ993]

anyone has any ideas?

[LogicalDrm]

For most 3pin fans 30% is lowest possible speed. For PWMs its 20-25%. Installing GPU shouldn't matter for power delivery at all. And definetly not on higher end board like that one. In your situation, I think it is more about how much GPU has changed CPU temps and how they  fluctuate. So since both fans are working, there isn't really any problem. Its probably more about how tight fan curve you have set.