Myth--Folklore or absolute 100% fact?

[JEDIYoda]

ok...I have been doing some reading and for the life of me as a mega heatpipe user....
I honestly have seen no,,,nada,,,el zilcho differences in the direction that I mount my particular different coolers...up..down ..sideways it has not made any sort of a difference in the temps at all~!!

Thats why I entitled this thread...Myth..Folklore or fact?

Please if you have facts from "knowledgeable and reputable" reviews sites or from your own trial and erro please let your opinion be made known......

If you mount your hsf with the heatpipes on the bottom side, which would mean that the liquid pools in the pipes and doesn't make contact with the heatsink's base (or even the fins for that matter).

Someone told me that they are running the same CPU at significantly lower temps on a mobo where the XP-90 was rotated 90 degrees compared to the regular mounting method!

I truly believe that where the liquid starts out in the closed system has no bearing on the heat dissipation as long as the base of the Heat sink is flush with the CPU making contact!

Okay...I started this thread...

Please post opinions...Thank You!!

 

[Operandi]

The only position that should have a significantly negative effect on performance would be having the heat pipes in upside down manner as the liquid would pool in the opposite end of the heatsink.

The only real world occurrence I've seen this in (not personally) is using this Asus board in the Lian Li V series cases due to the northbride heat pipe heatsink being upside down.

 

[Zarubable]

As long as you mount the heatpipe and it makes good contact with the CPU you can mount your heatsink anyways you want.
If this was such an important issue why do none of the heatsink manufactureres mention this in there brochures or on there websites?

 

[grimlykindo]

I say MYTH!

I have an XP-120 on a DFI Nf4 Ultra-d, which forces me to install it upright (heatpipes hanging down) - which is "suppose" to be bad :roll:

My 3200+ Venice temps:

idle: 28
load: 38 (6 hours of Prime95) :Q

I have also tried laying my case on its side so the xp-120 is laying the "correct" position (like a desktop PC) - N

*NO CHANGE IN IDLE OR LOAD TEMPS!*

IMO these are some INSANELY low temps for an air setup (I know people with mid-level watercooling that have very similar temps)

So basically what I'm saying is that heatpipe direction makes no difference (well, at least with my XP-120)

 

[JEDIYoda]

hmmm...wrong topic....arrgggg

 

[GalvanizedYankee]

I linked this in Zap's thread re.heatpipes and will do it here because it IS worth the read.
heatsink-guide.com click on heatpipes at the left. Read it twice slowly. I did! This is not a current posting but all the essentials are there,ie.type of fluid, matrix used for capillary action,material used in constuction,etc. There is even a link to the manufacturing process that i did NOT read. Marketing is a big part of this and anyother hot
game in town. A heatpipe HSF does not need to be mid-tower case filling to be VG. But being huge and shiny sells. I will be buying a HP-HSF in the near future, not sure what way i'm going on it.

Read the link, young JEDI :-D


Galvanized

 

[Zap]

Originally posted by: JEDIYoda
ok...I have been doing some reading and for the life of me as a mega heatpipe user....
I honestly have seen no,,,nada,,,el zilcho differences in the direction that I mount my particular different coolers...up..down ..sideways it has not made any sort of a difference in the temps at all~!!

Thats why I entitled this thread...Myth..Folklore or fact?

What, my thread wasn't good enough for ya? 😛 I've somewhat concluded that properly designed heatpipes will work in nearly any direction due to capillary action if the interior of the pipe has some kind of wicking mechanism. Some directions may or may not be more efficient than others but should be "close enough."

Originally posted by: Zarubable
If this was such an important issue why do none of the heatsink manufactureres mention this in there brochures or on there websites?

I think I've read about the motherboards with Northbridge heatpipe cooling needing to be mounted in a "normal" fashion and not "upside-down" as in the V series or Temjin. Also, the Scythe Katana heatsink instruction sheet basically states that it shouldn't be used with pipes pointing down.

Originally posted by: grimlykindo
So basically what I'm saying is that heatpipe direction makes no difference (well, at least with my XP-120)

I think one reason why it may not matter as much in a unit like the XP-120 is that those pipes are bent around, so even the "best" orientation would have parts of the pipe horizontal (theoretically not best nor worst). Perhaps it matters more with straighter pipes such as those in the heatpipe Northbridge coolers or the Scythe Katana - unlike other tower heatpipe coolers that have pipes horizontal, the Katana can possibly be oriented so that the pipes point down.

Originally posted by: GalvanizedYankee
I will be buying a HP-HSF in the near future, not sure what way i'm going on it.

Looking for pure performance or budget? The original XP-90 (not the all copper version) is a good relatively budget unit. Next one up would be the Scythe Katana or Arctic Cooling unit (forgot name), but the AC unit uses a proprietary fan.

 

[GalvanizedYankee]

In all honesty Zap. After seeing the pic at the bottom of the HP article at that link, the wheels
started spinning. Pushing air away from the mainboard is a *cool*deal. Cooler air would be drawn past the MOSFET/NB with passive sinks on them. So the SI 120 sure looks good.
Stand back! The wheels may fly-off 🙂 It could be in budget in a month.

JEDI, in your collection of HP HSF i know you have a SI 120,iirc.
Question, will a pair of 92mm fans slide under it's wide wings?? Looks like a pair of 80s will
with ease. I would super-glue two 92s together, after a lite sanding of the sides and PVC
grommet mount them on home-made brackets w/ducting to the NB 😛.



Galvanized

 

[Zap]

That may not work too well because the heatpipes will be just over the "dead spot" of the fan motor.

 

[BonzaiDuck]

A web-search would turn up that white-paper I found last year at a corporate web site. I can't remember the name of the company, but they first produced heatpipes under NASA contract.

The original design called for the product to work in complete weightlessness. So I would think that whatever effect gravity has on the various positions for mounting your cooler, it either cancels itself out, or it is negligible.

 

[Zarubable]

**BUMP**

 

[kleinwl]

The orientation of any heatsink (not just those with heatpipes) doesn't make any difference by itself. The only way that the orientation makes a difference is when it causes a change in the overall case. Ie. is the heatsink in a cooler part of the case due to airflow.

 

[BonzaiDuck]

Kleinwl

Your points are well taken, but this issue has been bandied about for at least the few years heatpipe coolers have been available in the enthusiast-PC market.

The Myth assumes that condensed coolant at the far-end (cool end) of the heatpipe will form in droplets and that these droplets will then slide down the heat-pipe and pool over the hot part of the pipe, vaporizing, and re-iterating the cycle. Then, the orientation of the pipe would matter, or the droplets would have to defy gravity. The Myth assumes that heatpipes oriented with their cold-ends at a lower level to the ground than the hot-ends, will have coolant pooling in these areas without distributing the coolant back to the hot-ends -- due to gravity.

But the History of HeatPipes indicates that the pipe was designed to work in the absence of gravity -- hence, the method of delivering liquid coolant to the "hot" zone could not rely on gravity at all, but on wicking and capillary action. If this was the method deemed "most effective" in the absence of gravity, it stands to reason that it would have "some degree" of effectiveness in the presence of gravity, or that it might encounter the same limits under gravity that it encounters in complete weightlessness.

 

[kleinwl]

Bonzai,

The effect of capillar action is 10x (or more) times as strong as the effect of gravity. So, in the gravity zone there may be a small, but unmeasurable, difference in efficency.

 

[BonzaiDuck]

Well, that cinches it. The "Myth" is much ado about Nothing.