Would I be exceeding the PCIe lane supply with this build?

[CyberScy]

I have a Maximus VIII Formula board with a 6700k and I plan to have two cards in SLI (980ti's).

Would adding an M.2 SSD (x4) to the mix mess things up regarding the PCIe lanes available? Some sources say Z170/6700k has 16 lanes, where others say it has 20. I'm not quite sure which is true. Also, I don't plan to add anything else on the PCIe slots. Any advice would be appreciated, thanks

 

[Dark Lord of Tech]

*1 The The M.2 slot shares bandwidth with U.2 slot and SATA Express 1 slot.

 

[BadActor]

They have 16 PCIe lanes and 4 PCH lanes.