Submerged liquid - what temps for mobo?

[mike]

Hi,

I am thinking of doing a submerged ln2 run in the near future and was wondering what the lowest temps for the motherboard should be? I read in several post that boards have coldbugs. How cold can the northbridge generally go?

Thanks

PS would love to hear what liquid you guys would recommend that isn't too messy/oily - rather alcoholly...

[Disposibleteen]

the safest liquid for submerging out there is call flourinert made by 3m. It costs around $500 a gallon though. Submerging a whole motherboard in ln2 wont work though, if im not mistaken the caps dont like the cold, someone correct me if im wrong on that one though.


Edit-
Caps stop working at low temps because there is a fluid inside them.

Stole that from another thread, guess i remember correctly.

[Rauf]

thats right...caps can't handle more than -40C if I remember correctly.

[charlie]

http://www.xtremesystems.org/forums/showthread.php?t=52004&highlight=trapped+ice

[mike]

Thanks for the replies. I wasn't that clear - actually wanted to mobo to be submerged in a liquid - which is partly cooled by the ln2 container for the CPU and if needed a bit of extra ln2...

I am in Florida and it can get kinda humid - occasionally... So it's mainly for condensation - but also for a bit of extra ommph.
I would like to find a setup only make some occasional test runs - I will not have the system submerged for any long periods.

Ultimately I wanted to try to build a vaccum case - but this might bring downsides in terms of heat-transfer of various components like mosfets etc.
Replacing the air with another gas might be a solution but if there is an easy and cheap liquid it would make things much easier.

Charlie - I read your article with enthusiasm! Great run!
My concerns with your liquid was on one hand potentially the price - and also how involved the cleaning of the components could be. I am looking to test a lot of different components and I hate cleaning up...
- Am I wrong about this - how involved is the OPTI-COOL clean-up?

Fluerinert sound perfect - just the price is an absolute no-go.

Something along the lines of rubbing alcohol would be great - low freezing point - no clean-up after a couple of hours of fun. I am not sure whether the rubbing alcohol could do any damage to any components and whether there really would be concerns for a fire hazard using it?

[v4p0r]

rubbing alcoholconducts electricity and will not work You will short everything out. Im using Non-conductive mineral spirits. You can pick it up a lowes or home depot fairly cheap. as for the lns im using mine with DI and a rigged up radiator deal. Took the whole 5 gallons subzero. My lowest temp with DI was around -5 degrees Farenheight. The system works pretty well because i can keep my chipset cpu and gfx card really cool. Im Keeping the rig submerged 24/7 without other cooling and it stays at room temp (70 degrees) at full load. Im currently working on a 24/7 chiller for it Made out of an old freezer. I noticed it getting kind of thick at subzero temps. So im thinking LN2 might be too cold. Although i dont know if it would hurt anything if it did freeze solid. just remember to pull all of the fans because if it does freeze it will screw the fans bad. I have the fans on the cpu and GFX card still figuring they add some flow. Ive been working submerged for about 2 months now and i think its gonna be the next wave in cooling. Good luck. And be careful. Test any liquid you want to try to use on an old Power supply or a radio or something before putting your mobo in it. And remember till you trust the liquid unplug before touching th liquid. Good luck and take care

[Disposibleteen]

wait a minute, you run your HDD array under mineral spririts???? This cannot be good for the internals, it would put more stress on the moving parts than normal and probably lower the lifespan of your drives drastically.

[Bloody_Sorcerer]

actually, booze-soaked harddrives don't die. I've seen harddrives run naked (IE, without their casings) for extended periods of time whilst drenched in vodka. In a normal air environment, they die in around 5 days (when naked)

[v4p0r]

No my hds are actually in a rack above the spirits. I know i shoulda worded that better.