@infi most manufacturers do not publish the idle power consumption of their cards, but from what i understand they all run relatively low. i think it would take a considerable amount of time (years more than likely) to recoup the costs of the lower power cards. if i am wrong on that i would love to know about it, as i too am interested on the impact to my bottom line. @fodder the medieval warm period lasted for hundreds of years, and yes it was part of the natural variation. what we have now is also part of the natural variation (a warming since the little ice age), as evidenced by the 15 years of cooling that we have had (which, incidentally, matches the 15 years of reduced solar activity the we also experienced). your argument still hinges on a positive feedback loop, which i have shown does not hold water. taht 1 to 2% max retained radiation can easily be drowned out in the noise of natural solar variation, which has shown fluctuations of 10 to 15% across all spectrums. your claim of a "finely balance system" also hold little wight, since science cannot even identify all the variable in play, let alone say for sure what future trends hold. what we do know it is is a very chaotic, non-linear system that has a number of know negative feedback loops that have prevented thermal runaway in the past, that co2 levels are not "at their highest levels ever", and a ther may be a few theorize positive feedback loops that don't hold water on closer inspection. couple that with all the know benefits co2 has on the biosphere, and the argument for co2 being a "dangerous pollutant" look silly. grats for having the guts to stand up for what you believe, but please attack my argument rather than reiterating a point that i have show to be invalid.