Ok the question, i have three monitors 2 are hooked to the dvi connectors on the 5870. I don't feel like buying a $100 active adapter for the display port to DVI for my third monitor. So i used my old 8800gt for the third monitor. The problem is the fan on the 8800gt is always at 100% i tried using rivatuner it detects the card but whenever i go to lower the fan speed it doesn't do anything? Is this because i have a 5870 installed.
I also just ordered a second xfx 5870 for crossfire and i heard that you have to have all three displays on one card? If that's true then hopefully i can find away to lower the 8800gt fan speed.
You will not be able to utilize eyefinity if you connect a monitor to the 8800gt. You also can't use eyefinity unless you use the displayport connection or buy a active adapter for it. For the fan issue it may be faulty or maybe its because it is not the primary card. You could try uninstalling and then reinstall rivatuner to see if it clears up the problem. I am not the most experienced with rivatuner, so maybe someone with more experience with rivatuner can help you.