ASROCK Z97 Extreme6 EFI issues booting from XP941 M.2x4

Mar 18, 2013
ASRock Z97 Extreme6
GTX 770
Mac mini
Mobile Phone
Android, iOS

I have XP941 M.2 x4 for about a year far but still can not manage to boot from it. ASRock Z97 Extreme6 acts very strange - with CSM disabled there is no way to see any EFI boot drive except and until the USB 2.0 EFI boot flash drive is plugged. After that there are multiple entries show up for all my drives (including SATA, SATA SSD, M.2x4 and USB) if using F11 boot screen, but if I physically remove any SATA drive - the boot entry either stays or becomes BLANK(!). Also in the boot section of the BIOS itself I can see LOTS of repeating entries in groups of either blank or showing non-existing drives, sometimes this BIOS boot section can somehow grow up to 40-60(!) entries all together. Only clearing CMOS or Re-flashing the BIOS will clean that list. I am using BIOS V1.70 but have also tried all newer versions up to 2.30 with even worse results (e.g. when booting into UEFI BIOS it becomes extremely slow with 3-5 seconds response delay to the input no matter if I am using PS/2 or USB mouse and keyboard with all USB compatibility options turned ON).

I ended up with using regular SATA HD as actual boot drive (since I am using it anyway as destination for Carbon Copy Cloner for OSX YOSEMITE) and M.2x4 drive as actual media to load OSX.

Is there any way to make the XP941 M.2 x4 drive bootable itself? I have exactly the same partition/content for this M.2 drive and SATA SSD and regular SATA HD. The only regular HD can be seen in the BIOS (apart from the USB 2.0 stick).

Once booted to CLOVER, ALL my drives with whatever OS installed become perfectly visible (M.2x4, SATA/SSD, SATA/HD, USB 3.0) and I can load whatever is installed on them...

PS And yes, the INTEL NIC failed on the second day so it looks like this motherboard has a common issue with it.