Fan types and differences.

[AsRock]

Just wondering if there's much difference when the blade count is higher or lower.

For example you see some with 3 7(typical) or even more and how this effects the noise level of the fan. I'm think ing that more blades would course less noise due to each blade would be moving less air right ?.

so if you have a 3 fans that are the same but have different blade count which be the better do you think ?. and for what it be better for.

Another question is whats the best fan if it's close to filter heatsink for a few examples as some say there more made for that sort of thing all though i dought it that it makes all that much difference.

EDIT: Forgot to add that noise to one is different to another person like sound from a hifi. So that said just after what you think is better.

Different fan blade count make different tones of sound ?. would this be the best way of thinking ?.

 

[kiriakost]

Nice subject for dialog , but cheap as presentation .

Instead of starting a dialog from ground point , you should had to investigate more ,
throw about 60$ getting and testing some fans , and then we will talk about the details.


I have do that ... spent money ... we all did ... how in earth we will get an opinion with out losing money.

 

[oli_ramsay]

http://www.madshrimps.be/?action=getarticle&articID=892

Here's a HUGE fan roundup. Hope that helps.

 

[karlotta]

Nice subject for dialog , but cheap as presentation .

Instead of starting a dialog from ground point , you should had to investigate more ,
throw about 60$ getting and testing some fans , and then we will talk about the details.


I have do that ... spent money ... we all did ... how in earth we will get an opinion with out losing money.

Anyways, Silent PC has good info too.

 

[Silverel]

Just wondering if there's much difference when the blade count is higher or lower.

For example you see some with 3 7(typical) or even more and how this effects the noise level of the fan. I'm think ing that more blades would course less noise due to each blade would be moving less air right ?.

so if you have a 3 fans that are the same but have different blade count which be the better do you think ?. and for what it be better for.

Another question is whats the best fan if it's close to filter heatsink for a few examples as some say there more made for that sort of thing all though i dought it that it makes all that much difference.

EDIT: Forgot to add that noise to one is different to another person like sound from a hifi. So that said just after what you think is better.

Different fan blade count make different tones of sound ?. would this be the best way of thinking ?.

I've got tons of screaming fans.

From my experience, fans with lots of blades are almost always audible, regardless of the speed they run at. It is a significantly different sound, and at high speeds (where all fans should run anyways), I find they are more prone to fade into the background. Less blades with larger surface area are more ideal for lower speeds as they can typically go inaudible. I use a 13-blade fan on my second rig to cool a 2600XT. At full speed it hits about 4k RPM's, and you can hear it from across the room. A similar 6 blade fan at the same speed will cause additional vibration due to larger amounts of pressure being created by the increased surface area. It's this vibration at high speeds that makes the sound unpleasant to me. A fan with more blades will split up that pressure.

Another point to make, is that fans with more blades are more apt to blow INTO things, whereas larger blades are better at sucking air out. Intake/exhaust fans should be larger/less blades, whereas a CPU/GPU with the fan blowing into the HS will see better returns with more/smaller blades.

Noctua had an interesting design with their fans that can decrease the pressure on large blades by adding precise notches. It allows them to act closer to a fan with more blades, without causing the same sounds, and also reducing the vibration. Only problem, is they're incredibly ugly.

There's tons of information on teh internets. You'll never know which one sounds good to you until you hear it though. Occasionally some review sites will take a recording of the fans at different distances, those would help to determine which sounds good to you.