Using Radiators to Cool CPUs 245
dan writes "Overclockers Australia have a review up of the CPU Radiator Zen, a new approach to cooling your toasty CPU's. Rather than taking the traditional approach of a heatsink with lots of fins and a noisy 7,000rpm fan it uses radiator/heat pipe technology. The implementation of the unit is a bit flawed, but it is interesting to see where the technology is heading.. and if it can be done right I personally think this is where it will end up."
Silent? (Score:3, Interesting)
Radiator=water=dangerous! (Score:1, Interesting)
And, my Athlon 1,5Ghz will instantly boil any water because it's ONE HOT MAMA!
Heat pipes have been in use for a long time (Score:4, Interesting)
Twinhead advertising claims that their heat pipe technology is patented. I've no further details and couldn't find anything relevant on their web site.
Buy Windows XP. Give Bill Gates even more of your money.
I still like the homemade jobs (Score:2, Interesting)
http://www.overclockers.com/tips672/
http://www.overclockers.com/tips699/
Other reviews (Score:4, Interesting)
The reviews are all favorable, but it's not clear whether this is simply because the reviewers are blinded by the "hey, it's neat!" factor, or whether the Radiator Zen SCR325-2F actually has a legitimate technical advantage. But hey, it is neat, so I can't blame them.
so it would work! (Score:2, Interesting)
Re:Noisy Fans? (Score:2, Interesting)
Fans make noise. Period.
I'm one of those individuals who are simply driven mad by excessive computer noise which means that anything over 50 dB is intolerable. In fact, some time ago I sold my 600 MHz Duron PC because I couldn't stand the noise the CPU fan alone made. A CPU fanless Sun Blade 100 with a low rpm hard drive was heaven after the previous noise polluter (the power supply still makes noise, though). I'm quite content with the trade-off I had to make between computer speed and noise.
I still blame the CPU manufacturers for ignoring the heat problem (=noise problem) at the altar of unnecessary performance, though.
I wonder... (Score:3, Interesting)
it's all conditioning (Score:2, Interesting)
I doubt this thing actually does anything... (Score:4, Interesting)
I mean, you have a radiator which exposes the same surface area as a typical heat sync, but makes less effective contact with the heat source.
The fluid is probably not doing anything significant at all, the two fans gushing past the aluminum tubes is probably doing all the work.
I don't even think this thing is actively cooling. There doesn't seem to be any pump... they're relying on the thermal gradient to cause the vapourizing fluid to move to the cool side of the radiator and condense. It doesn't work that way. You need to have some way of forcing the fluid to move in one direction, you need to cause the liquid to vapourize by forcing it through a small opening, pulling heat from the CPU.
If you can somehow get around that technical wizardry, then you have to find fluids which vapourize at the temperature of the CPU, but condense at the temperature on the other side of the radiator... whatever wimpy thermal gradient that might be... the pressure of the system also remains constant because the whole system is operating passively of course.
In other words... if you have a CPU at 50 degrees C, and your cooling fluid vapourizes at 40 celcius, then the other side of your heat sync MUST remain lower than 40 celcius, otherwise you just have a bunch of tubes full of pressurized vapour. There is no reason for the cooling side to actually cool especially if the same area is exposed to the CPU as is exposed to the fans.
On the other hand, if your fluid vapourizes at 60C, it doesn't actually DO anything until the CPU reaches that temperature.
This is not to say that passive refrigerators do not exist, I just don't think they've built one. They've built a chunk of aluminum full of fluid with two fans blowing through it.
They should have run another benchmark: Drain the radiator.
Kryotech has this done right.
conductivity of water (Score:3, Interesting)
Minor nit pick
The conductivity of water is based purely on the impurites in it. If you had truely pure distilled water, it would not conduct.
I used to work on a transmitter that had water cooled voltage regulator tubes. They regulated many tens of thousands of volts with big wattage. You measured the purity of the water by the measuring the electric conductivity in fractions of micro-mhos [dictionary.com]
Alpha prototypes had this too. (Score:2, Interesting)
They needed a liquid with a high heat of vaporization, and a boiling point in the 30-50C range. They tried mixtures of water and alcohol, but settled on just water, pumped down to 1/3 ATM.
They went looking through the "steam tables" and found that nobody had ever looked at the sub-atmospheric range of pressures, and had to derive all of the thermodynamic properties themselves.
It was pretty quiet, but made a funny little 'tick' noise right when it started boiling.
More details at http://www.research.compaq.com/wrl/techreports/ab
and http://www.research.compaq.com/wrl/techreports/ab
-Jeff Bell
Old news? (Score:2, Interesting)
Re:Thermal generator runs against thermodynamics (Score:2, Interesting)
E.g. with a cpu running at ~50C, and a liquid with a boiling point of, say, 40C, you could build a little steam engine, letting the steam condense at room tmperature for the 'refill'. Voilà.