HP spectre x360 stuck in sleep mode. power button flashes on and off when power button is pressed.

[KingBing]

My computer froze then shut off. The computer will not restart or enter the prelaunch using the escape key to go to the BIOS to reset the BIOS. When the power button is pressed it makes a noise every couple of seconds like it is starting up or the fan is coming on then is stops within 1 second. The computer screen does not turn on.

[Echo_Lake]

@KingBing

Thank you for posting on the HP Support Community.

Don't worry as I'll be glad to help, however, to provide an accurate resolution, I need a few more details:

• Did this happen after a recent window or software update?
• Have you made any hardware/software changes?
• Did you make any changes to the settings of your PC prior to the issue?
• When was the last time it worked fine?

While you respond to that, let's try these steps: 
Hard Reset: Follow steps from the link: https://hp.care/2GnkMa8. (do not skip any troubleshooting steps even if you feel steps are repeating)

BIOS default: 

1. Turn off the computer and wait five seconds.
2. Press the Power button to start the computer and repeatedly press the F10 key to enter the BIOS setup menu.
3. On the BIOS Setup screen, press F9 to select and load the BIOS Setup Default settings.
4. Press F10 to Save and Exit.
5. Use the arrow keys to select Yes, then press Enter when asked Exit Saving Changes?
6. Follow the prompts to restart your computer. If the computer does not power on then you need to service the product.

Hope this helps! Keep me posted for further assistance.
Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution.