I have an intel NUC 5i7RYH which is running a Samsung XP941 PCI-E m2 ssd. I've been keeping up with the bios updates for this unit, but after flashing beyond BIOS 0249 I've been unable to boot from the m2 SSD. It's still listed as a boot device, but it will only boot from a UEFI boot device on these later bios versions. It will no longer boot a legacy OS on this drive. This is the same for 0348 and 0359 BIOS. I've gone through all of the settings multiple times. Once I go to BIOS 0348 or 0350 I can only boot from UEFI boot devices. Even an external USB DVD drive will no longer boot the windows install DVD using legacy mode. The same for the Acronis True Image CD. If I switch and use the UEFI boot for those devices they function, but I'm no longer able to boot my M2 SSD using the legacy installed Windows 7 that is on it using any bios after 0249. I've down-rev flashed down to 0247 and 0249. They all return proper boot function for legacy devices and I can boot the m2 card again.
Also, for all of the above BIOS versions, if I enable xHCI (auto, or enabled) my mouse and keyboard stop working in windows after rebooting from the Linux install. I have to do a full power down and back on to make those devices work again.
I noticed in the release notes that the version for the sata option rom was changed in version 0348 which is where I started having problems.
In BIOS 0249 it was v13.5.0.2164.
In BIOS 0349 they upgraded to 14.5.0.2241
I'm back on 0249 without issue other than I can't enable xHCI or my mouse/keyboard stop working after switching OS on a reboot.
Can anyone else confirm my issue with the Legacy boot issues with the Samsung M2 card using a BIOS after 0249?
Can anyone at Intel provide some feedback or support on this?
Thanks.