We are now able to find out what kind of power is being used by our test system and the associated graphics cards installed. Keep in mind; it tests the complete system (minus LCD monitor, which is plugged directly into an AC wall socket).
The power consumption of the X58 Extreme from ASRock with the i7 975 at idle was not too bad. It is actually a little less than what I have seen from a Core 2 Quad running on an X48 board. What is a little bothersome is the huge delta between idle and load power consumption. We saw the power draw from the wall jump over 130 watts in each case. So the X58 Extreme is power efficient when it is resting, but not so much when you need to put it to work.
As a new measure, we are now monitoring the heat generation from the key components on the motherboards; this being the Northbridge, Southbridge (if it contains one) as well as the Mosfets around the CPU. The results are recorded at idle and load during the power consumption tests.
Heat is not too bad here and is about what you would expect given the cooling system used. Bear in mind that these readings were taken on an open system. Once you put the X58 Extreme into a case and close it up these temps will certainly go up. This is especially true if you chose to use water cooling as the heat pipe system will have to rely on air movement from any case fans you may have.