Passive cases for Mini PCs

Urgannagru

Trash Compacter
Original poster
Sep 28, 2017
34
5
Hi, Currently working on a build (not sure if I can cross post but a thread I posted regarding it is here https://smallformfactor.net/forum/threads/specification-creep.3390//), and while going through the process I keep coming across other ideas I'd like to investigate.
The most recent of these are mini PC's along the lines of the zotac magnus 1060 and Alienware alpha, now the Magnus seems an incredible machine but well out of my price range (though I've seen an En31050 on their site which should be cheaper and still potent enough for me but can't find it for sale anywhere or much mention of it anywhere anyone seen a release date mentioned anywhere).
The alpha however seems within my range and potent enough despite the older hardware, the biggest flaw for my uses being the volume of it's cooling. Looking into it abit though it seems like it could potentially be passive cooled via a heat sink case, the first version (r1) has a total tdp for the cpu and gpu of around 75w, around the claimed effective heat dissipation of the FC8, the R2 I'm less sure of with the gpu being alot more power hungry (not sure on figures but guessing around 120W but might be possible with a separate larger heat sink.

I have no experience of this but I'm wondering about the viability of using flat heat pipes such as those by amec thermasol, would using the existing heat blocks to sandwich the heat pipe work as the screw system looks fairly simple, though the vrms of the gpu would not be in direct contact with the heat pipe and would relie on the existing heat blocks to transmit the heat to the pipes via thermal pads. The heat pipes could then be bent at right angles to spread the heat to heat sinks forming the sides of the case such as these http://uk.rs-online.com/web/p/produ...VbSjTCh3v0AjhEAkYAiABEgKZLfD_BwE&gclsrc=aw.ds

To secure the heat pipe I'm thinking a couple of strips of aluminium across the pipe and screwing in the case wall. Down sides of this method would be the heat being spread vertically up the heatsink rather than across the whole width, a possible plus point would be retaining the original heat sinks which would add to heat dissipation and if the passive cooling was not effective enough a large slow moving fan could be added extract air via the top of the case.

Sorry for length to could it short my 3 main questions are:
1) Is the idea generally viable?
2) Do you think it could work with the more power hungry alpha r2 aswell as the original?
3) Anyone heard anything about the Zotac Magnus en31050?

PS, Pity the GPU and CPU aren't lined up otherwise a single heat pipe could be used to to the entire job and it could be put straight into the FC8 with some motherboard standoffs added.
 

msystems

King of Cable Management
Apr 28, 2017
781
1,366
Anything is possible. If the side of the case was just a giant heat sink such as this it might work. I remember from the spec sheet those flat heatpipes are most effective when the condenser end is vertically above the evaporator, so somehow the orientation of the case or heatpipes should be done to optimize that. I believe I saw a thread around here reporting success with these heatpipes in the DB4.


Edit: http://www.amecthermasol.co.uk/datasheets/MHP-2550A-100A.pdf

See page 2-3, esepcially the "Qmax vs Tilt" chart. If I am reading this correctly, heat transfer limit increases from 75 to 270 watts when used in a vertical orientation.
 
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Urgannagru

Trash Compacter
Original poster
Sep 28, 2017
34
5
Cheers for replying, when I stumbled on these forums your fc5 along with hulksters fc8 got me rethinking my original plans and reconsidering what can be done with passive cases, really inspiring stuff.
Those graphs look promising as a tilt of just 5 degrees should in theory allow enough thermal transfer for even the 960 and hopefully leave enough vertical distance for a decent surface area with the case wall. Will be a bit of a balancing act to hit the sweet spot but considering how even a small tilt can have a large impact it looks promising.
Any ideas for spreading the heat horizontally along the case wall or do you think the natural thermal conductivity of the aluminum would be sufficient?