my question is whether the Cold ambient would allow the TEC Block to perform better.
from what i have picked up... the colder you can keep the HOT Side, the Colder the COLD Side will be?
That is what I meant when I said "The sheer volume of copper in Ultra's block will make it pretty efficient at low ambients."
I did not make myself clear enough.
If you can provide sufficiently chilled coolant to back up the cold the block can hold you are on to a winner. With a sufficiently cold HOTSIDE you don't have such a high Dt requirement to get a really chilly coldside. This allows the use of smaller TECs or bigger ones with a good undervolt - the advantage of the undervolt being greatly increased efficiency once you go a little below 45% power. Of course if you want to maximise the coldside temp you could use a large TEC at more than 50% power thus trading your efficiency for greater Dt - so long as your working Q exceeds the heatload of the CPU by a fair bit.
Edited by zipdogso - 11/28/09 at 6:46pm