750 series SSD performance on CPU, or PCH PCI-E

[CBark1]

Where can I find more data comparing the performance of an Intel 750 series ssd (1.2TB HHHL) operating on native PCI-E lanes from the CPU vs PCH supplied lanes. I'll be using a 6700K on a Z170 chipset motherboard. I am trying to determine the penalties caused by the DMI bottleneck, and if it warrants the upgrade to an X99 board.

[NMICH1]

They test out both here (on a samsung drive, not an intel one) :

http://www.myce.com/review/native-z170-hyper-m-2-vs-pcie3-m-2-77791/ Native Z170 Hyper M.2 vs PCIe3 M.2 - Myce.com

and find no difference.