Hi,
as this is no typical BSOD / Win crashes
it's not the correct location to ask for help.
However the message "INACCESSIBLE BOOT DEVICE" indicates win can't load the correct driver for NTFS/ AHCI or (because) the partitiontable is damaged.
Win8.1 always comes on an UEFI-System, along with Secureboot enabled in Bios, otherwise it won't boot and you get a message from your Bios.
Given that, the partitiontable is damaged.
TestDisk - Partition Recovery and File Undelete might be the chance to inspect and probably correct the failure.