Ed Trice (liquidnitrogenoverclocking@hushmail.com) on 6/22/11 wrote:
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Welcome to our forums!

>On the last page of the article, there was mention of "lowering the CPU temperature
>with liquid nitrogen or a Peltier to around 5C could yield >even larger gains" but this is in need of some rephrasing.

Fair enough, I made a correction.

>We've worked with liquid nitrogen a fair amount, and temps are closer to -200C (see http://www.liquidnitrogenoverclocking.com/news_03.shtml
>for example).

When you say -200C, what are you measuring? I'm talking about the junction temperature of the chip. I suspect you may be talking about something else, since I think silicon behaves oddly at those temperatures. But perhaps I'm wrong...

>As for Peltier Cooling, our experience has shown that you can't get more than a
>40C difference compared to the ambient temperature.

A peltier is a heat exchanger, there's no reason why it needs to simply use the air to dump out heat. What about a Peltier that pumps heat to the liquid nitrogen? You could get a much larger surface area that way.

>So, it would be much easier
>for a Peltier device to hit 5C in the winter somewhere >cool than in the heat of summer.

>Peltier devices are also very inefficient. It costs you >about 10 times as much
>power to remove the "heat equivalent." By that I mean to >pull away 50 Watts worth
>of heat would cost you 500 Watts worth of input power. >Clearly, this is not the way to go.

I'd agree with that, but it's an option.

David