Bling Bling why don't they thunk it?

[Zebo]

I have built a HSF which cools better and is quieter than the current models available. The key is a larger diameter fan (120mm) vs. the typical 60 or 80mm on most modern HS. The 120mm can push more air at with less noise. I modified the alpha shroud intake to accept a 120mm fan I made from aluminum sheet metal. Now I'm running 33C under load 1.0@1.5 10X150.. VS 47C before with the loud as .... delta it came with.


Why don't these HSF companies do this? Quieter and cooler is what we want. Is it the cost?

 

[Guilty]

Because it doesn't actually work. These are sold of course, people have tried it before. The problem is the airflow is less than fully effective due to the friction it's hitting. Plus in some cases where the shroud doesn't cover the entire fan, the air is then blowing onto the socket and affecting the reading device to show cooler temperatures than the core is in reality.

 

[Zebo]

All the air is sucked through the HS up threw to the fan . It's a closed system. I used sheet metal and sealed the contacts points with silicone so I don't see how this could be less effective. BTW- the HS is now 6" tall!!!

^^^^^^ airflow
^^^^^^

||||||||||||||..Fan
\............/
..\........./
...\......./
....||||||...HS

 

[Noriaki]

There is a slight problem.

The hub of the fan actually has minimal airflow behind it and that is centered over the heatsink....but that's not the biggest problem, the main problem is pressure gradients, you end up trying to pull a lot more air through a small hole.

120mm fan worth of air through a 60mm hole...thus you end up with a pretty severe pressure gradient and fan performance is actually decreased becuase axial fans don't perform well under pressure (pun intended).

The idea has merit, but it needs quite a bit of work.

The best way to do it would be to get a heatsink with an 80x80 fin grid.

But you are right 120mm fans definately push more air at less noise than a 60mm fan, and it may be that it's enough more to overcome the disadvantages and it ends up cooler.

It's certainly much quieter, which is nice.

Good luck.

 

[BD231]

Theres a much more effective way to cool a hot system. I use the presure factor:The more air presure there is, the more air is forced to move around(circulate). I have an Antec SX-1030B with 4 28cfm fans, all of which blow air *into* the case. My Athlon XP stays around 34C at full load with a VERY poor(but extreemly quiet) hsf, with the fan blowing onto the heat sink. I have found this solution to equal and sometimes beat the performance of a delta based HSF, there is simply no better way to cool a computer quitely.