I have a new toshiba satellite p855-s5312 that I havent been able to boot up since i took it out of the box... i have tried almost everything possible tried a new AC adapter, I tried all the different ways to reset it using the power button and removing the battery and holding f8 and have come up with nothing. The battery is good and i
this can happen normally. wait for 3-6 minutes to boot. but if it doesnt work. turn off the laptop by hold one of the function keys, push f2 again and again untill you see your BIOS screen, go to Security, then go to Secure boot, change to "Disable" then go to advance and go to System Configurations and click on the one that says CSR, change it to UEFI. this should work
Does it do anything when you press the power button? If not, something on the mobo is broken and do a RMA. If it goes into a bios screen or says no bootable media, then I suggest opening the hard drive cover and check to see if the hard drive is loose.