Shrink Way Wielder
- Feb 22, 2015
The total system - CPU+GPU+TECs - is what will consume 700W+. TECs need a ton of power to pump heat, and it scales with both the heat load and temperature difference.Fair point.
But what single GPU and CPU combo consumes 700w? Max this will need to realistically cool is 350w I would have thought?
How a TEC performs is referred to as its Coeffecient of Performance (COP), and it varies based on heat load and delta-T (hot side minus cold side). Here's an example of a COP graph for a typical TEC:
A COP of 1.0 means it takes as much power to move the heat as the heat load. That is, if the heat load is 350W, the TEC needs 350W to move that heat. We see that on this particular graph, it hits a COP of 1.0 at a delta T of around 32C. The higher the delta T, the lower the COP, such that at a 50C delta T it's now below 0.5, or twice as much as the heat load being moved.
Now remember, any power being used by the TEC is heat that will need to be removed. So at that 50C delta T we now have the original heat load (350W), plus 700W being used by the TEC. That's 1,050W of heat that you now need to get rid of. You see how this quickly becomes a problem, and why "below 0 cooling" in a 5L case strains the limits of credulity?