8 Krypton

RE: XPS9560 Bios 1.2.4 bricking systems

A member of the NBR forums (you get real help there) has found another way round, hold the power down for at least 25 seconds, the charging light will flash, let go and leave it alone while it resets the bios and recovers itself.

You may need to reconfigure the BIOS after as it will be in RAID mode.