Custom (very) Quark esc heatsink...

[zeropointbug]

GriffinRU, I know all the limitations about heatpipes...

They really do have to be tuned to a specific operating temps, and ambient temps.

I know this first hand.... frozen CPU.... i've done this before in the winter when it's -35C outside, with the PC case in the window, the CPU will get to below O temps, by doing this, you can get VERY high overclocking levels! Last year I took a Pentium 4 3.2 Northwood (130nm) to a sky high 4.25ghz! That was with a solid copper heatsink though.

THIS year, with my new PC with a large tower heatsink (Noctua NH-120) I did a cold window test, although only -15C, and the initial temps went down to about 5C, after a few mins of running the temps started to go up and up, until it hit 55C... hotter than what it gets at room temp! So they are definately sensitive to ambient temps. My guess is that the vapor just froze up and physically BLOCKED the vapor chamber.

I guess it all depends on the pressure of the working fluid for a certain temp range. Diameter, and length have to do with energy transfer.

Every couple months, manufacturers come out with new heatsinks, most all the new ones are heatpipe ones. The new Thermalright Ultra-120, and their IFX-14. The IFX uses biggest 8mm heatpipes, and uses 4.

If you had the room, the more heatpipes you can fit at the heat source and lower vaporizing temps the better, and evenly spacing the pipes into a fin radiator.

It's all in the design!