Topic: TriFire water cooling (was: Squeezing 2-slot cards into a single slot) - page 5. (Read 10549 times)

Compression fittings aren't exactly cheap either.  You won't save much.  For 4 cards you will need 12 compression fittings (excluding the "outside" fittings to connect to rest of network.  The small amount you will save will be paid in pure frustration trying to get it to fit together.  Also mounting the cards will be a lot of "fun". The SLI bridge connectors provide some strength to the multi-GPU package making it easier to install and uninstall (looks like one giant 6 or 8 slot GPU) .

I think now you might be realizing why I said if you can get good price of 5970s then selling the GPU for 5970s makes sense.  You only need 1 waterblock for each set of GPU.  4 GPU = only 2 cards = 1 bridge not 3.  All those things start adding up.

Basically watercooling has such a high unit cost per element being cooled you want that element to be as expensive and powerful as possible.  Dual GPU cards are a perfect fit.

Thanks D&T, those are about what I was coming up with too, I wasn't sure if the '1-slot' they were referring to actually meant 'blocks in adjacent slots', guess it doesn't.  It looks like the Feser ones could work.  I was looking at some similar fittings from DangerDen but they only came in a pack with one set of fittings and three tubes of differing length - for $12... and I'd need 3.. 

All the fittings and connectors and odd and ends are adding up to be almost 1/4 of the total cost, it's insane!

I'm kind of thinking that I'll just go with tubing and compression fittings for now - I've read that it's a total pain in the ass to get the tubing length just right, but it should work just fine and won't impact flow rates much.  The XSPC compression fittings I'm looking at are pretty low-profile, so I think I can squeeze two of them and a small chunk of tube between the blocks. 

Of course I've thought lots of things lately and been totally wrong

Um I can double check when I get home but I believe they are these.

http://www.frozencpu.com/products/10742/ex-tub-667/Bitspower_SLI_Crossfire_Multi-Link_Adapter_Pair_-_Black_Sparkle_BP-BSWP-C47.html?tl=g30c101s873

and these:

http://www.frozencpu.com/products/10744/ex-tub-669/Bitspower_SLI_Crossfire_Crystal_Link_Tube_Set_-_2_Slot_Spacing_BP-CLTAC-S2.html?tl=g30c101s873

They work great but bad news is they don't make a 1 slot connector (i.e. no space between blocks).  


It looks like something like this would work for cards in adjacent slots.
http://www.frozencpu.com/products/8566/ex-tub-448/Feser_Crossfire_SLI_Multi_Spacing_Fittings.html?tl=g30c101s873#blank



Here is the whole category of toys:
http://www.frozencpu.com/cat/l3/g30/c101/s873/list/p1/Liquid_Cooling-Fittings-Accessories-SLI_Connectors-Page1.html

Someone needs to try this with mining ! EPIC !

Back to the OT if I may - it turns out those Swiftech universal GPU blocks end up taking up 2 slots as well.

I think I'm going to end up going with the full-coverage blocks just to keep things more open in the future.

DeathandTaxes, what fitting are you using to connect your 5970s blocks?  I'm having trouble finding what I need..

and I was wrong.  They did submerge the power supply as well.  Obviously this keeps things running cooler but the power use is gonna be much higher.  I don't know how you would make that work for larger scale mining operations without killing your bottom line.

Yes!

http://www.pugetsystems.com/submerged.php

These guys?

[edit] Guess that link is a bit old, but still relevant - they're up to 'V4' now: http://www.pugetsystems.com/aquarium-computer.php

I wish I had the link.  There is an outfit that is selling computer aquariums that they have soaked in mineral oil.  They were on their second or third iteration, which each being something like 2-3 years and going strong.  I remember them saying even the fans were ok.  The only thing they didn't submerge were the power supplies and the hard drives. They mentioned trying a bubbler to help with the diffusion, but I can't remember if they said it helped or hindered. 

That is a valid point. Did anyone so far do this and test out of the PCB remains solid etc. ?

Probably not if you used distilled water, but mineral oil is hydrophobic.  You'd need some kind of detergent to bind the oil, like dish soap. 

You wouldn't be able to just dunk it either as the water would seep between the PCB layers and make quite a mess.  Come to think of it, the mineral oil probably will too. 

Any way you look at it, submerging your card in some kind of liquid isn't something you can just do on a whim and expect to turn back.

Well would they corrode or something if wash them with water and let them dry ?

I'm not sure anyone's actually taken the leap, but it's been talked about a few times.

The general consensus is that it's not worth destroying your cards for the ePeen factor.  Once you dunk them in mineral oil you're certainly not going to be able to resell them, your warranties are null and void, and they become rather difficult to clean up and use outside the mineral oil bath.

There's no reason it wouldn't work, but the downsides tend to steer people away.

Mineral oil cooling for bitcoin. Anyone try it ?

Sometimes I think you're just making up half these colloquialisms on the spot

Anyway - submersion is a viable solution, the trick to keep the VRM/RAM/GPU from overheating are big fat heatsinks on the chips - they work the same submerged as they do in air - and pointing an (also submerged) fan at them/on them to push fluid around.  

In the same respect the stock HSF boxes would work, but you'd burn out the fans pretty quickly moving around anything more viscous than air.  Of course, this is still combined with pumping all the fluid through an external radiator.

I think running a few tubes around and spot-cooling is a little less messy though

Hardcore?

This is hardcore (sorry Jarvis) - rip the whole badly-designed BS off these cards and install them single-slot-style, in a logic board suitably modded to accept 4 cards without bumping into heatsinks etc. (or remove the heatsinks from the logic board).

Then dunk the entire logic board and cards into a tub full of some liquid that has both *incredibly* low electrical conductivity and *incredibly* high heat conductivity. Some pipes, a pump, a feck-off big heat exchanger and a very large, quiet fan (or multiple fans - whatever is required to pull air through the heat exchanger *quietly* but efficiently and, importantly, move a LOT of air) - job's a carrot's second cousin.

It could be that the heat density of both the CPU and GPU cores, plus certain components on the graphics boards that I'm *sure* cause me all the aggro (e.g. XFX put a nice heatsink on the GPU, but the bits that overheat are bare, uncooled RAM chips or VRMs) is simply too high for convection in a bath of inert fluid to be adequate cooling.

Would this be so? Hell - even with a broken fan, the components will hit over 100˚C but have logic built in to prevent 400˚C accidents. I'm not talking about using water (polar, too conductive even if 5 9s pure), or burn-the-house-down diethyl ether (hehehehehe) - but something that boils significantly over 100˚C and doesn't conduct electricity even when hot.

Even if the heat density causes hotspots, this can be solved easily enough because with the cards perpendicular to the logic board, a fluid pump positioned sensibly should cause a steady flow of cool (straight from the heat exchanger) fluid over the cards.

I'm not talking cryogenic fluids here (that'd be *extreme*, not *hardcore* ) - the entire rig should work at room temperature. High boiling point for the inert coolant is desirable to minimise evaporation - but a sealed system is also more feasible if the fluid isn't prone to high vapour pressure in the computation tubs - if the coolant isn't anywhere near boiling, a sealed system would be a LOT easier since pressurisation isn't anywhere near as high in the engineering problems to solve.

Apart from the warranty issues - the whole idea of home-brew water-cooling using waterblocks, home-made piping and domestic pumps / heat exchangers seems insane to me. Some of the biggest hot-spots on GPUs are small components like VRMs and capacitors. Most water-cooling systems put copper waterblocks over the GPU and memory. None of them can give a cool surface to ALL components, especially not the small but high-heat-density ones. So I'm bemused as to why the hardcore haven't tried to use the full-immersion cooling system more frequently.

Is it *really* that hard to find a suitable liquid coolant that is both electrically non-conductive (even accounting for potential contaminants, e.g. if the fluid is hygroscopic) and conducts heat well enough to serve as a coolant in a heat engine?


I've seen the few *extreme* types with bare PCs inside tubs of liquid nitrogen, etc. but those tend to be built 'because I can' rather than because the system really needed it. One of the old Cray supercomputers actually *had* the requirement for full immersion liquid cooling, rather than just the CPU. High-density computing such as bitcoin mining with lots of modern GPUs consuming many kilowatts in less than a cubic metre... I'd say that is getting very close to the point where full-immersion cooling would present *real* benefits.

Is anyone doing this in anger? Are there kits available, and have the bugs been worked out? I'd be keen to remove all the heatsinks and fans off my GPUs and put the *whole lot* into a tub full of inert coolant if the job was feasible. There's more heat capacity in a tub of coolant too... if the pump were to fail then I'd have more time for the machines to shut down before the coolant boiled off - it's not like our GPUs are nuclear fuel rods, but with just convected air, a powered GPU will burn out before software can stop it (hence the panic switches *on the silicon*)...


Bit of a hardcore option, but if these are *dedicated* miners.... Just chucking some ideas around, given my problems with cooling at the moment...

Full coverage waterblocks cover entire card including all VRM, GPU, PCIe bridge, and other components.

Immersion cooling works but isn't economical.  There are very few low conductive fluids that have higher thermal conductivity than plan ole water.  The few that are have incredibly high price tags.  Mineral oil is a good medium cost heat transfer fluid but is roughly 10x the cost of distilled water and has 1/4 the heat capacity.

Not sure where you get the idea that waterblocks can't keep video cards cool.  My GPU are <50C and VRM are <70C with a 18% overvolt.  

What limits further overclocking isn't temp so some ultra complicated and expensive immersion rig isn't going to get higher throughput.

What limits further overclocking is:
1) I don't have any desire to push higher voltage through card which is necessary to push clocks over 1Ghz.
2) As voltage increases power consumption increases by the square so I don't max overclock my cards anymore due to simple economics.


Thermodynamics tells us that would be bad.  Any immersion fluid while it may have higher conductivity than air has much less conductivity than copper.  You would need an astronomical flow rate (think giant sump pump) to avoid the chip cooking before it can transfer that thermal energy into the fluid. 

Air is a fluid.  You already have immersion cooling with air.  We use copper heatsinks because they can transfer that thermal energy from the die very quickly.  Even waterblocks which use have thermal conductivity have a decent amount of copper to spread out that point energy source.  Remember a GPU not only emits 200W+ of thermal energy it does so from an area tinier than your finger nail.

Nice watercooling tips here but too bad it is not really that cheap.

Yeah I am thinking of getting one of those someday.  Expensive but certainly has a lot of cooling capacity.

I was going to go with the DangerDen tubing packs, seem to be highly regarded, nearly or just-as flexible as the Tygon, and way cheaper. 

I'm planning on getting one of those 9x120mm monster radiators so I'll have plenty of headroom for nutzo overclocking and such, and the CPU will be part of my loop as well.  Good call on hanging it outside during the summer!