Hi all,
I thought I'd seen a thread about this somewhere on this forum but I can't seem to find it again... Did an unsuccessful search... My apologies if this is a double thread.
Anyways, here is my question :
Wouldn't it be better to mount the fan slightly away from the heatsink (like a couple of centimeters) ?
It would spread the airflow through the heatsink more evenly and put an end to the dead spot in the center of the fan (where the rotor is). As far as noise is concern, I'm not sure...
Any thoughts on that ?
best way to mount a fan on a heatsink ?
Moderators: NeilBlanchard, Ralf Hutter, sthayashi, Lawrence Lee
equalizing the airflow so that there's no "dead zone" in the center is a good idea but if you simply move the fan away from the sink, all you get is lower air pressure. that would drop the cooling efficiency.
the best method for what you are looking for is ducting. you can do it with a gutted fan, just like thejamppa said, you can rig your own duct (look through the forum posts for an example, there's plenty), or there are some commercial ducts available that you could use.
there are also fans that are designed to minimize this "dead zone" but none of them are on SPCR recommended list. I did have good results with a voltage-regulated (through m/b) delta tri-blade slow 120mm but it's not used often around here.
another group of fans to look at is the 38mm-wide variety. there's lots of disagreement about their effectiveness-to-noise ratio but two things are for sure - they do have better air pressure than 25mm-wide fans and they do create a bit more turbulent air-flow thus minimizing the "dead zone".
the simplest thing you can do, of course, is to mount the fan you have a little bit off-center and see if the temperatures would improve. i used this method before, it worked pretty good for me. not as good a ducting but there was a noticeable improvement.
the best method for what you are looking for is ducting. you can do it with a gutted fan, just like thejamppa said, you can rig your own duct (look through the forum posts for an example, there's plenty), or there are some commercial ducts available that you could use.
there are also fans that are designed to minimize this "dead zone" but none of them are on SPCR recommended list. I did have good results with a voltage-regulated (through m/b) delta tri-blade slow 120mm but it's not used often around here.
another group of fans to look at is the 38mm-wide variety. there's lots of disagreement about their effectiveness-to-noise ratio but two things are for sure - they do have better air pressure than 25mm-wide fans and they do create a bit more turbulent air-flow thus minimizing the "dead zone".
the simplest thing you can do, of course, is to mount the fan you have a little bit off-center and see if the temperatures would improve. i used this method before, it worked pretty good for me. not as good a ducting but there was a noticeable improvement.