Corrupted HP BIOS

[TNHo]

Some time ago, my HP Pavilion TouchSmart 20-f394 All-in-One Desktop PC suffered a bad BIOS 
update and won't boot.
I tried all the things on HP's website to try to recover the BIOS, but none helped.
I attempted the Award BIOS Recovery, but that pc doesn't have a floppy drive, so I attempted to do it on a USB, but it doesn't work. 
I also attempted this method on a CD, that also doesn't work.
Is there any other way to recover the BIOS without buying a new motherboard?

[GautamGehlot]

How about trying to use the Hardware Diagnostics UEFI on the original computer to update the BIOS？

[TNHo]

How about trying to use the Hardware Diagnostics UEFI on the original computer to update the BIOS？

No, I can't do that, all my PC shows is just a blank screen.