How cool can a waterchiller keep a cpu under load?

Perfect_Chaos · 22 Jan 2007 at 00:50

With the chiller set so it goes to ambient temp, that way no condensation. How would the temp be on a Quad overclocked and under load? so if ambient was 27 or 28c in summer, how would load temp be?

and how much better over regular water?

Martynt74 · 22 Jan 2007 at 01:01

Of the chiller was set to ambient temps it wouldnt give too much of an improvement over normal water.
If you dont wanna be bothered with condensation etc theres not much point bothering

Perfect_Chaos · 22 Jan 2007 at 01:15

Marvt74 said:
Of the chiller was set to ambient temps it wouldnt give too much of an improvement over normal water.
If you dont wanna be bothered with condensation etc theres not much point bothering

well this sucks then

Martynt74 · 22 Jan 2007 at 01:19

Then do what men do and insulate away

Perfect_Chaos · 22 Jan 2007 at 01:21

Marvt74 said:
Then do what men do and insulate away

i was hoping to get great temps without the insulation, had enough of that before my Mach broke.

Messiah Khan · 22 Jan 2007 at 09:30

Perfect_Chaos said:
i was hoping to get great temps without the insulation, had enough of that before my Mach broke.

Get normal water and a big rad then.

pastymuncher · 22 Jan 2007 at 09:45

Waterchillers were originally designed for the aquarium industry and mainly used in marine tanks were constant temps are essential. We are talking in the mid 20's. If one of these is hooked up to a water loop that is cooling high spec cpu and gpu chips then there is a chance that one would eventually burn out. They are not really designed to get rid of that much heat. Basically they are a fridge and removes the heat from the water. Couple that with an extremely high purchase price and high running costs and it really is'nt worth doing.

Much better to go with high end water and stick the rad in a window.

Messiah Khan · 22 Jan 2007 at 09:55

pastymuncher said:
Waterchillers were originally designed for the aquarium industry and mainly used in marine tanks were constant temps are essential. We are talking in the mid 20's. If one of these is hooked up to a water loop that is cooling high spec cpu and gpu chips then there is a chance that one would eventually burn out. They are not really designed to get rid of that much heat. Basically they are a fridge and removes the heat from the water. Couple that with an extremely high purchase price and high running costs and it really is'nt worth doing.

Much better to go with high end water and stick the rad in a window.

You do know you can get waterchillers designed for cooling high load computers don't you? Im fairly sure they wouldn't burn out any time soon if built properly. The problem with them though, as mentioned is that they generally are designed to cool the coolant down to ~-20degrees C, which means insulating the whole loop.

pastymuncher · 22 Jan 2007 at 10:25

messiah khan said:
You do know you can get waterchillers designed for cooling high load computers don't you? Im fairly sure they wouldn't burn out any time soon if built properly. The problem with them though, as mentioned is that they generally are designed to cool the coolant down to ~-20degrees C, which means insulating the whole loop.

No i did'nt actually.

But from what you say they are designed the same way to cool down to the low 20's. They must still be expensive to buy and run all the same, and then as you say, it would all need insulating as well.

Messiah Khan · 22 Jan 2007 at 10:44

pastymuncher said:
No i did'nt actually.

But from what you say they are designed the same way to cool down to the low 20's. They must still be expensive to buy and run all the same, and then as you say, it would all need insulating as well.

that minus 20 btw.

They are essentially phase change cooling systems with a coolant heat exhanger instead of a evap head. Although you can get ones with an evap AND a chiller built in.

Starfall · 22 Jan 2007 at 10:52

Who built the chiller system?

As you have temperature control in guessing the chiller is using either hysteric control with capillary tube/TEV or just a CPEV.

Remember dew point will always be a few C below ambient and high airflow over the sub ambient area will decrease the point when condensation becomes a problem further...

Messiah Khan · 22 Jan 2007 at 10:56

Starfall said:
Who built the chiller system?

As you have temperature control in guessing the chiller is using either hysteric control with capillary tube/TEV or just a CPEV.

Remember dew point will always be a few C below ambient and high airflow over the sub ambient area will decrease the point when condensation becomes a problem further...

You asking me? I don't have a chiller, I was just saying that they are available. I do however have a shiny new phase unit.

Starfall · 22 Jan 2007 at 11:04

No, the OP

I do however have a shiny new phase unit.

Cool, did you make it yourself?

Marci · 22 Jan 2007 at 11:14

In answer to the OP's original question, how cool can a chiller keep a cpu under load...

Wattage of the chiller and it's thermostat will determine how cold the coolant gets. c/w figure for the waterblock at given flowrate will determine the CPU temp as ([WATTAGE HEATLOAD]x[C/W])+[COOLANTTEMP]

Fictitious example - Chiller capable of removing 300w of heat, with thermostat to keep coolant at 5 degress below ambient. Assume ambient of 25 degrees.

So, coolant temp = 20 degrees C.
We'll assume our QX6700 cpu is kicking out 130w of heat (at stock).
We'll use the Apogee CPU block, with a flowrate of around 1.5gpm, which gives a C/W of approximately 0.0375 (see http://www.swiftnets.com/assets/images/products/apogee/TR vs FR.gif)

So, (130x0.0375)+20 = 24.8 degrees C

As you overclock the CPU, wattage increases. Assume a 3.5Ghz overclock with 1.55v...

(263x0.0375)+20 = 29.8 degrees C

As long as heatload remains below 400w, chiller will keep coolant to 20 degrees C. If you give it a heatload higher than 400w, the chiller will never cool it to thermostat temp - you're overloading the chiller. It'll run flatout 24/7 and won't do much chilling.

Messiah Khan · 22 Jan 2007 at 11:14

Starfall said:
No, the OP

Cool, did you make it yourself?

Ah, ok.
Nope, Gray Mole did;
http://forums.overclockers.co.uk/showthread.php?t=17681715

Starfall · 22 Jan 2007 at 11:23

Very nice!

That must be one of Grays last builds..?

Messiah Khan · 22 Jan 2007 at 11:30

Starfall said:
Very nice!

That must be one of Grays last builds..?

Possibly. I think he wants to get back to playing for himself. ie cascades etc.

Perfect_Chaos · 29 Jan 2007 at 12:27

Well apparently i dont have to worry about condensastion when going below ambient, it only happens depening on humidity & what temp you set..

so if it was 20c ambient and humidity was at 50% i could set the water chiller to 9,3c without condensation.

water chillers seem really good, and im looking at gray mole for one right now.. not only that but temps are adjustable and can be from around -20 to +30.. in other words i could use it below ambient without condensation and if i feel the need to extreme cool the gfx + cpu i could just insulate and turn the chiller temp right down

overall i expect it to be a lot quieter and a lot more efficient over regular water, no big fans for a low temp (which aint possible on regular water anyway!) so maybe a 20c difference over regular watercooling

Marci · 29 Jan 2007 at 12:41

overall i expect it to be a lot quieter

Make sure you sit it on a bed of rubber sheet then - compressor vibration means it'll make about the same noise as a MachII...

Messiah Khan · 29 Jan 2007 at 13:22

Although you will be able to get it quiet, your deffinately not going to get it quiter than a standard watercooling setup due to the compressor and condensor fans etc.