for a 550ti an 8x8 slots will not slow down 550ti sli at all, I think a 5870 is reduced by 2-3% in an 8x lane which is generally about the same performance as a 6950 to give you an idea, I'd say up to gtx 560ti is good to run on an 8x slot without too much performance decrease from the 8x slot versus the 16x, so basically you will be absolutlley fine to run 559ti sli on your current mobo @ 8x8
Ive heard of people running 5770 on 4x slots pretty well just to give you another frame of reference
do you have any sort of excessive micro-stutter issues? just wondering bc I'm switching back to 6870s myself and I've had problems in the past... how is the overall experience? sorry not to hijack the thread but thought that this info might be pertinent
Microstutter on CF'd 6870's pertinent to SLi'd GTX550's? How does that work?