[Sadden]

So its about that time for a new rig, my I5 2500k is starting too show its age, and theres all kinds of goodies out there now.

Im deciding between a i9 9900k and Threadripper...

I have a really great dew point (-4 too -6 dewpoint) as our air is really dry up here, and am considering doing a water chiller on the loop. Id like too start on the cpu (preferably with a quality monoblock) and after a few months of success with that id also like too chill the video card(s).

My question is which brands of waterchillers get the coldest, it seems like many of the cut off around 4c? I would like too insulate things well and eventually drop too sub zero for daily use but i don't really know whats brands are decent and what are not.
Also what size of unit would you guys recommend for something truly insane like say 2990wx and two 2080tis etc.

 

[ShrimpBrime]

You're in the wrong section. You want to go to Phase change. Click the first thread and read the second post. It gives a good hint. Anything you buy, the bigger the pump the better. 2HP is pretty good start. The more you want to chill, the bigger you want that pump. (The chiller pump not the water pump.... but that too )

 

[Sadden]

Thank you for the feedback, maybe a mod would be kind enough too kick this over there for me.

I found an AquaEuro 1HP unit that uses R22 (boils at -40.8)

Current plan is too run a loop into something like a yeti cooler, with some kind of thermostat hacked into it so i can leave it running fulltime. Shoot for maybe -30c or so, so it doesn't get too inefficient. Then too have the water cooling loop run off the yeti type cooler.

 

[ShrimpBrime]

-30c is pretty cold. Would you be chilling acetone then?

Honestly, with the temps your going to try and achieve, you may be much better off with a phase change cooler and eliminate the use of a water loop all together. This is the route I think you should go, and easily hit -30c for a daily use.

Here, check out this video.

 

[J7SC]

-30c is pretty cold. Would you be chilling acetone then?

Honestly, with the temps your going to try and achieve, you may be much better off with a phase change cooler and eliminate the use of a water loop all together. This is the route I think you should go, and easily hit -30c for a daily use.

Here, check out this video. https://www.youtube.com/watch?v=4d0B0Dli-1g

I have a powerful phase change cooler which I used on a 3770K, 4790K and 6700K - it worked great. However, on HEDT 6 cores / 12 threads and up, a single phase cooler cannot react fast enough to load changes, IMO. With the OP mentioning 2990X and such, he would need a multi-stage phase change cooling setup which can be very big, bulky, loud and use a lot of electricity.

Re. chillers, there are several good water chillers on the market a different price points (ie by Alphacool, Hailea, Koolance) and providing up to 1500w cooling capacity

 

[ShrimpBrime]

I have a powerful phase change cooler which I used on a 3770K, 4790K and 6700K - it worked great. However, on HEDT 6 cores / 12 threads and up, a single phase cooler cannot react fast enough to load changes, IMO. With the OP mentioning 2990X and such, he would need a multi-stage phase change cooling setup which can be very big, bulky, loud and use a lot of electricity.

Re. chillers, there are several good water chillers on the market a different price points (ie by Alphacool, Hailea, Koolance) and providing up to 1500w cooling capacity

Yea, I suppose a cascade would be better fit.

For big temp swings, plate between the cpu and cooling head generously

 

[Sadden]

Yeah I definately have no plans on doing a multi stage. Thats why i want too just use a decent water cooler and shoot for mild sub zero temps. Maybe i only reach -20c under load doesnt reeally matter too me. Unsure on fluid yet. Will depend on what the water block compatibility is like. I havent researched that yet.

The whole goal with running a large reservoir like a yeti 35 or 45 is too allow the chiller too operate as it normally would full time. I need too get a unit in hand and see how they work so i can hack a thermostat into it too allow it run as normal except at sub zero temps. That large reservoir also means the loop will be able to handle large spikes easily so long as im running a decent pump.

 

[ShrimpBrime]

-30c is pretty down there for 2/4/7. You will be dissipating mad amounts of heat into the room it's located in, unless you dump the heat outside. Just something to think about.

Hacking a thermostat is ok I suppose. But you should want the pump to cycle. So if the chiller pump and condenser are large enough you could make that happen. But when a pump continuously runs, the coolant in your large res may start to gel or freeze around the evap. That's why at the temps you seek, it's important that the coolant doesn't freeze and there's a nice flow inside the yeti chill box.

I've experimented with this type of chiller before. It's difficult. I won't do Acetone like that though. Used automotive coolant which is typically good to -20c maybe -30c but always gels up on/around the evap.

 

[Sadden]

-
30c is pretty down there for 2/4/7. You will be dissipating mad amounts of heat into the room it's located in, unless you dump the heat outside. Just something to think about.

Hacking a thermostat is ok I suppose. But you should want the pump to cycle. So if the chiller pump and condenser are large enough you could make that happen. But when a pump continuously runs, the coolant in your large res may start to gel or freeze around the evap. That's why at the temps you seek, it's important that the coolant doesn't freeze and there's a nice flow inside the yeti chill box

Im not talking about a chill box. The yeti is only a resevoir for whatever fluid the chiller is chilling, too give a large buffer for help absorb temp spikes, and too allow the chiller too cycle on and off as normally. The units are meant too cool several hundred gallons.

The chiller itself will be located in an unheated crawlspace. Worst case scenario it preheats the air for the furnace lol.

I do want the pump too cycle, thats the whole purpose of hacking a seperate thermostat into it, as the oem thermostat on them only runs down too about 4c or so. And all the sub zero hacks i have seen just have the unit run fulltime when the pc is powered on. So i need a way too be able too tell this thing too run down tooo -20 or -30c and turn itself off, and then cycle back on again as needed.

Our ambient up here gets down too -40c pretty regulairly, i have easy access too a pile of different fluids that wont gel off at those temperatures. The other cool part of having such an extreme climate is my dewpoint is pretty low.

 

[ShrimpBrime]

You're giving me ideas with that crawlspace. Like a geothermal built loop. However you won't get -30c from that, but would pre-chill the liquid and help achieve those temps making it easier to get your desired results. This is my idea/opinion. I run a Geothermal loop and use that to chill a TEC. I was able to bring chip temps down to about -30c. However a full load was closer to the freezing point perhaps a couple c above after a period of time. The end result made a cooler running processor with a little better efficiency able to run a slightly lower voltage, but did not increase any max stable overclock. I also am runnign a B450 chipset and that very well may play a role in my chilling adventures.....

That said, either processor you choose and decide to overclock will not be so easy to keep chilled at only -30/40c.

Since you're not using the Yeti to place a evaporator, I'm curious how you are going to chill the liquid? A second Yeti for a chill box perhaps?

 

[Fisbwp283]

I'm building this project at the moment as well.

I have a 25L reservoir with the refrigerant coils and an agitator pump rated for cold glycol...the type used to chill beer fonts and make them frost over.

If you want the CPU @ below zero, than you need fluid 20-30 deg below zero as a minimum. this is the real challenge as non-toxic fluids that are low viscosity at that tempreature are a real challenge to find. if a loop temp is at low 20c, then CPU temp at load is at least mid 50's....so the delta of chip to fluid is 20-35c in continuous operation as a best case scenario, with a fluid (water) that has the best heat capacity...as you get fluids with colder freezing points, the heat capacity also goes down and they are less efficient. this is the reason why industrial chillers most commonly only achieve @4c, as to go below freezing gets extremely complicated and its easier to chill water in bulk to near freezing and then use that chilled water in a specialist process to go lower for specific applications...eg as the start of an industrial cascade...

Ethanol and Methanol based heat transfer fluids are great candidates for low viscosity low temperature fluids, but for me are not worth it due to vapour pressure build up in a closed loop or off gassing if you go for an open loop.

for 24/7 use, with non industrial pumps and non toxic fluids, you are realistically limited to -10c and Propylene Glycol.
@ 0c - 40% PPG is 4 times as vicious as water at room temp
@ -18c - 40% PPG is 15 times as vicious as water at room temp (Freeze point is -24c). beyond 15 times the viscosity of water you need specialised pumps and custom blocks as the pressures really go up.

for Methanol @-20c the viscosity is about 1.5 that of water at room temp..but you will have issues with toxic vapour in an open loop. in a closed loop you might have issues with vapour pressure build up, so you need probably a 50% mix with distilled water, which then gets you a -50c freeze point..though not sure of the cloud point, but still has issues with vapour and vapour pressure.