MSI X99S SLI PLUS Intel USB 3.0 to disable xHCI

MSI SLI PLUS X99S   Bios 1.3
MSI Geforce 970 GTX /   344.16
Motu Ultralite MK3 Hybrid /  Drivers : 1.07
G.skill DDR 2400 mhz 16 GB
Intel INF Latest drivers.
Directx 9.0 installed
USB all drivers installed ( Asmedia, VIA and Intel)
WIndows 8.1 PRO

Ok th...