Not sure if this belongs in the motherboard or GPU forum section. I posted in both a moderator can delete the one in the wrong forum section.
System info :
EVGA X99 Classified E-ATX motherboard
Intel 5930k custom water loop
16gb G. Skill 2666 DDR4 RAM
EVGA SuperNova P2 1000w power supply
2x EVGA 980ti Classified


I installed 2x EVGA 980ti Classified GPU's a few weeks ago. They are installed in slots 1 and 4 EVGA's product manual says these are the proper slots for 2way SLI on this board and they should be x16/x16 with the 40 PCI-E lanes from the 5930K. I have the extra 6 pin power plugged into the motherboard for the PCI-E slots. For some reason slot 1 is reading 3.0 x16 but slot 4 is reading 3.0 x8. Why is slot 4 x8 and not x16 like it is suppose to be?? Is it that the GPU just can't use the bandwidth ? I tried pushing the cards with Heaven benchmark, 3d Mark, Furmark and it stayed at x8. I have tried disabling the other PCI-E slots. I have both the m.2 slots disabled. I have no other hardware in any other PCI-E slots. I also noticed that in the Nvidia LED configurator that the card in slot 4 is reconized as card 1. I am not sure if thats normal or just a bug in the software. When I had my 780ti's in they always read x16 on both slots. I just can't wrap my head around this. I know there is no real performance gains from x8 to x16, but I bought the 5930k specifically because it had 40 PCI-E lanes. I would like to be able to use the lanes and hardware as stated in the product specifications. If anyone else can confirm this with a similar set up please do so. Any help or input would be appreciated!!! I can post any pictures or info needed.

I have them set to auto. I have also tried to force Gen 3 on slots 1 and 4 both result in the same x16/x8. I also tried just 1 card in slot 4 and it ran as x8.