If I have 2 970's in SLI @ 8x can I still plug in a sound card? or No?

Also! Anyone have any idea if "Supreme FX" is better than Recon 3D Core by Creative?

Take a look at your Manual the PEI-C lane distribution is: PE1-x16 (x8 if PE2 is used), PE2-x16 (x8 if PE3 is used), PE3-x8, PE4-x16 (x8 if PE6 is used), PE5-x1 and PE6-x8. Hope this makes since. You can run two gtx 970's at x16 and a sound card.

Put your video cards in slots 2 and 4. Put your sound card in slot 5.This will give you x16 on your SLI. This is for a Classified board. For FTW put your video cards in slots 1 and 2 this will give you x8 on your SLI. Put your sound card in 3 or 4.

Keep one graphics card in slot 1 it says 8x but its 8 lanes direct to the cpu

Peteo, this not incorrect. If you run a card in slots one and two they will both run 8 lanes to the cpu. If you SLI it is best to run your cards in slots two and four. Try putting your sound card in slot 5.

Dude, you just said the same thing I said. Slots two and four. read my post.

Randoo1212
from what I read, pcie 1 is 8 lanes direct to cpu.  All remaining pcie slots share the remaining cpu 8 lanes by way of the Plex chip. Z 97 cpu's only have 16 cpu lanes no mater what brand of mothbrd you buy. Its all a dog and pony show, all I know is my system works great! Way better than my x-58.

FYI, if you read my post on this in the 8x/16x not 16x/16x  thread it will all make more sense... For SLI on the z97 classy, it seems best to keep one card in slot 1, and another in slot 4. Putting both in slots 2 and 4 bottlenecks the whole process bc both cards will be "switching" through the plx chip which has only 8 lanes to the CPU... Again, this type of setup (with a direct 8x to the CPU) is similar to other extreme overclocking boards too (see the z87 maximus extreme)..

man oh man, its like ground hog day. Same questions over and over.
pcie 1 is 8 lanes to cpu  that's where I want 1 Graphics card.  Every other pcie socket (2,3,and 4) share the 8 lanes remaining lanes to the cpu.
Its the modulating plex chip switching it up at the speed of light to give the illusion of more lanes than there really are. For most of our needs this just doesn't matter.
I want breathing room for my 2nd gpu and run it in slot 4.

The plx chip expands the total amount of lanes from 32 to 48 depending on the board. It is the cpu that only has a 16 lanes total. Do you really think any board manufacture is going to design the plx to choke the system? Look up your processor on Intel there you will find the right information.

Combining three or four video cards on a Socket 1150 motherboard is, as said, not really possible. The trick involving the four lanes from the chipset is supported by AMD for CrossfireX, although it is definitely not recommended. Nvidia SLI simply refuses to work in this arrangement. Still, Socket 1150 motherboards with support for 3-way and 4-way SLI do exist. This is because manufacturers place a PCI-Express switch-chip on such boards, usually a PLX PEX8747. This chip is connected to the CPU through PCI-Express x16 and offers 32 lanes to video cards on the other side. This enables two cards to be controlled with 16 lanes each or four cards to be controlled with 8 lanes each.

The total bandwidth to the CPU naturally remains limited to the 16 GB/s offered by PCI-Express 3.0 x16. Because the PLX-chip can switch, it is possible for two installed cards to communicate at full speed, provided the other is not transferring data at the same time. More importantly, both cards can also send data to one another at PCI-Express x16 speed through the PLX chip. The same holds true when three or four cards have been installed, although in this case the speed naturally is limited to x8.