Now I know WoW doesn't support crossfire/sli, however I've been running the game in crossfire mode for the better part of a year (2x ATI HD 6970's) and it's been happily chugging along at 60+ (vsync enabled) fps the whole time.
I originally ran it with 1 card, but was getting around 40 fps.
Recently, in the last 2 weeks or so my fps has been dropping to around 25 in any area with smoke or fire effects and after trying for ages to work out what the issue was I disabled crossfire and boom constant 60 fps everywhere again even 25 mans or in SW at peak time!
Does anyone know if the game was tweaked or if there is some oddness in the latest drivers that explains this? It's not an issue of course I don't care if the game is running on 1 or 2 cards as long as I'm getting my 60+ fps I just found it very odd that 1 card can stomp all over the performance of both cards when a month ago it was the other way round O.o