Horizontal Heatpipe Testing

[Rocky Mountain High]

High-end CPU air coolers, such as Thermalright’s Ultra-120 and Tuniq’s Tower 120, depend on heatpipes to conduct heat to the cooling fins. In the Silent PC Review test methodology (http://www.silentpcreview.com/article46-page3.html), it appears that the motherboard is horizontal and the heatpipes are vertical. While a vertical orientation is ideal for heatpipe performance, this situation exists only in desktop installations. The vast majority of heatpipe installations will be in towers where the heatpipes will be horizontal.

Anandtech, in contrast, appears to test CPU coolers in a vertical tower where the heatpipes will be orientated horizontally. Anandtech’s reviews have this qualification: “All cooling tests were run with the components mounted in a standard mid-tower case. The idle and stress temperature tests are run with the case closed and standing as it would in most home setups.” – (http://www.anandtech.com/casecoolingpsus/showdoc.aspx?i=2981&p=3)

• Besides Anandtech, which reviewers test CPU coolers with heatpipes orientated horizontally?
• How much does a horizontal orientation diminish heatpipe performance?

 

[Impulse]

I think a lot of different sites, Silent PC Review amongst them, has tested this type of heatsink oriented both ways in the past and the difference was always negligible (never more than one degree, if that)... The question came up a lot a couple years ago when heatpipe heatsinks started coming out. The substance inside the pipes will usually work just as well regardless of how it's oriented really.

 

[mwin]

The gas inside should travel from areas of high pressure (where it's hot) to areas of low pressure (where it's cooler) regardless of orientation. Seems that way to me, anyway.

 

[mhaskell]

Heatpipe positioning has little to no effect on performance, the only thing that effects performance is large G forces such as in a jet or spacecraft.