My GTX 580 gets down to about 55 fps while playing BF3 on max settings. I really don't notice any lag during this time. I have it slightly OCd... 880mhz core clock, 1760 shader clock, 1994 memory clock at 1.075v.
I was going to add another 580 in SLI, but I wonder if I'll really see much difference playing BF3. Will it?
as long as you are getting 40+ fps,i don't see a big reason to add another card.sure sli will boost performance but will also cause-
more power consumption and other issues.
i would suggest saving up now and upgrade later,580 is a pretty powerful card.