Hello,
Did you checked already if you have the latest BIOS version? If not go to hp.com/support, select your country, and browse for your model / operating system, download the drivers for BIOS and update it.
Otherwise try to enter into the BIOS (should be at startup , pressing F10 or F2) and restore the factory default values. (/!\ be careful if you modified the boot order or the disks configuration /!\)