Help with heatpipes on a heatsink

[Ecliptic]

Gonna build a new rig soon and it looks like al the good heatsinks have heatpipes in them. OK, I understand the whole heatpipe concept - liquid in pipe vaporizes, rises to top of pipe carrying heat away, cools and falls back to bottom. I can see that working as long as the heatsink is standing upright. But after you install it on a desktop case and put the case upright, the heatsink is essentially on its side. The heat pipes don?t go up and down anymore, instead they are sideways.... how is it still effective? Especially all the "U" shaped pipes, wont the liquid get stuck on the bottom leg of the "U"?

 

[frostedflakes]

Any computer heatsink that is worth a flip will use a wicked heatpipe. What happens is the heatpipe has a wicking material inside that will soak up the liquid when it condenses and, due to capillary action, pull the liquid to the heat source.

I think some very early computer heatsinks may have used gravity heatpipes, but anything you can buy currently will be using a wicked heatpipe and is not dependent on gravity at all. I think effectiveness is reduced very slightly when the heatpipe is mounted on its side or upside down, but not significantly.

Check out the Wiki article on heatpipes as well, I'm sure it has a lot of good info.