Heat pipe orientation - 3C difference

[tomsresults]

I had a Tuniq Tower 120 Extreme mounted on my i2600K blowing air up. The heatpipes on this heatsink were vertically oriented and spanned a height of about 100mm.

I noticed that tipping my case forwards 90 degrees so that the heatsink's heatpipes became horizontally oriented dropped my temperatures by about 3C after a couple of minutes. The difference was detectable repeatably and I kept the case's front fan blocked while checking. So I remounted my heatsink with a 90 degree different orientation, blowing air out the back instead of out the top and with horizontally oriented heatpipes. Now under 8 thread Prime95 load I get about 54-55C at 4.4 GHz instead of 57-58C.

Does anyone have a similar experience with their heat pipes?
If this effect is generally true, it would be nice to put that in the sticky guide here.

 

[saint19]

That's general rule. air flow comes from the front of you case, so, cooler fans blows the air to the rear of your case.

 

[tomsresults]

I think the improvement I noticed is due to the physical orientation of the heatpipes and the effect of gravity on the fluid inside.

Unless physically rotating the case somehow changed the airflow speeds in it.

 

[Leaps-from-Shadows]

The effect probably depends on the particular heat pipe type, so it may not be universal. There are some coolers that you can't use in certain alignments because it would cause the heat pipes to not work at all, or not as well.

 

[ko888]

Does anyone have a similar experience with their heat pipes?
If this effect is generally true, it would be nice to put that in the sticky guide here.

What you have described is nothing new.

You just have to Google on "heat pipe orientation" and you will find that this effect has been observed and reported on since the first heat pipe coolers came onto the market several years ago.