PCI-E Rates for SLi

[colinicky]

Have been looking at motherboards & some spec as 2 x 16 mode even with 2 GPU's where as others drop to 2 x 8 mode with 2 GPU's , Is this going to give a noticable difference or is it to variable depending on the card s used ?

 

[WJA96]

It depends on your screen resolution. At 1440x900 the difference is negligible. At 2560x2048 it's about 20% slower with the 2x 8x slots.