I have an 8800GT, this one:
http://www.gigabyte.com/produc ... uct-page.aspx?pid=2720#ov Type A to be exact. The stock cooling was crap, made by Zalman, still crap. I've replaced it with Arctic Cooling Accelero S1 rev. 2 with no fans, even tho they reccomend them. The actual card is passive cooled but sits in an Antec Threehundred case with all the fan slots full and all fans running on low
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I get 130-140fps on my 1680x1050 but I've limited them to 60 because I don't see the point of more fps than the refresh rate of the monitor. (keeps the card cooler too). CPU is E8400 with FSB set to 400, not that it ever kicks in at full power anyway.
I say you look on reviews for the lowest power consumption regardless of the cooling and strap on some aftermarker passive cooler, the bigger the better.
Last time I checked, 5750 from Ati had a low enough power draw but still decent performance. Also I doubt that hybrid-SLI of yours will work with nVidia 200 or 400 series.