Secured boot enable with Windows 10

[LanreDipeolu]

I decided to test out Secured boot option and the computer refused to boot again. It came up with 6 beeps and start button turned red. 

Please assist. 

[Paul_Tikkanen]

Hi:

Sounds to me like you installed a video card that was not made for your HP PC.

What you are going to have to do is to unplug the PC, remove the video card, and hook the monitor up to the onboard video.

Plug in and turn on the PC.

Go into the BIOS and disable secure boot.

Shut down and unplug the PC.

Reinstall the video card, hook it up to your monitor, and you should be OK again.

You cannot enable secure boot with a non-HP video card installed.

[LanreDipeolu]

Thanks for your response.  While waiting for your response I opened the chassis up and removed the motherboard battery and waited for a while before putting it back. When I rebooted, the bois has changed to secured boot disable but the system refused to come on. It came with a blinking prompt and a blank screen.  It is from a problem to another.  Do you still want me to unplug the dual video card and use the motherboard video card as you have suggested?

[Paul_Tikkanen · Accepted solution]

You're very welcome.

That doesn't sound good.

I guess you can still try what I suggested yesterday.

The 6 beeps, red flashing light = video issue.

But now that it isn't doing anything, leads me to believe there is now a greater problem.

[LanreDipeolu]

REally.? You scare me 

I will yield your instructions. Only the motherboard does nor have DVI or HDMI. 

[Paul_Tikkanen]

It scares me because when you set the BIOS to its defaults by removing the coin cell battery, it should not have disabled secure boot and if it did disable secure boot as you said, then the PC should be working just fine.

You would have had to have video in order to see that secure boot was disabled, right?

So what happened that caused the PC not to do anything anymore?

If you have video, you do not need to remove the video card.

You probably have to reinstall the operating system, if all you are getting is a blinking cursor after you get past the HP welcome screen.