I wonder if this board supports the 750 PCIe ssd as a bootable device , run the latest firmware.
I am told that the 750 PCIe SSD drive has been tested with DZ87KLT-75K and it can indeed be used as a storage device but it cannot be used as a boot device. I am unsure whether this has anything to do with NVMe.
Intel® 750 PCIe ssd can be used as bootable drive with Intel® chipsets version z97 or later. Please review the link below.
http://www.intel.com/support/ssdc/hpssd/sb/CS-035481.htm Intel® High Performance Solid-State Drives — Booting an NVMe* PCI Express* Solid State Drive