P6735a Corrupted BIOS

[ethanrush1]

Hi,

I needed to update the BIOS to the newer UEFI version on the HP website, but during the process, the system hung and shut down. Since then the BIOS is corrupted with no signs of coming back to life (even temporarily).

How do I know the BIOS is corrupted?

8 long beeps.

If anyone has any advice, or knows which jumpers to fiddle with, please let me know ASAP.

Thanks in advance,

Ethan

[Lil_Boy_Blue]

Hi
Hopefully one of these documents will cover (and solve) your problem...
https://support.hp.com/ca-en/document/c00042629
https://support.hp.com/us-en/document/c02693833

https://support.hp.com/gb-en/product/hp-pavilion-p6700-desktop-pc-series/5035348/model/5036184/manua...
https://support.hp.com/us-en/document/c04126730

Power button LED blinks 8 times with 8 beeps

BIOS/CMOS  (ROM) problem,

Perform BIOS recovery with external media (USB/CD-ROM).

http://h10032.www1.hp.com/ctg/Manual/c01859455

Just shows HOW2 open etc.

https://support.hp.com/gb-en/product/hp-pavilion-p6700-desktop-pc-series/5035348/model/5036184/docum...

Main Board link.  Including clearing CMOS, so no need to fiddle you can fettle.

If in doubt please ask.

[ethanrush1]

Thanks for your help.

Unfortunately, since I can't get to the Esc menu, I can't update the BIOS. I need some way of flashing a BIOS to it manually or switching the BIOS to a known good version (which I can not do with Win + B since it is both old and not a notebook).

Any other ideas?

[Lil_Boy_Blue]

Hi

For a desktop this is a possible answer according to the link I posted from HP

To recover an earlier version of the BIOS on your computer:

1. Turn off the computer.
2. With the computer off, press and hold the Windows key and the B key at the same time.
3. Still pressing those keys, press and hold the Power button on the computer for 2 to 3 seconds, and then release the Power button but continue to hold the Windows and B keys until the BIOS update screen displays or you hear a beeping sound (usually 8 beeps).

It seems as though you are reluctant to reset the CMOS on the Main Board, which may solve your problem.

I can only find a single BIOS listed for your PC

IPISB-CH PC Desktop BIOS Update

7.15 Rev. A 3.1 MB Dec 21, 2011

So what/which BIOS you are going from / to  you don't state. 

So without more/better details I cannot help anymore.

[ethanrush1]

Resetting the CMOS didn’t help. I did try it though. 

I also followed your steps, but not much changed. I held down the right keys, waited for the 8 beeps and then just left it there to do it’s thing and nothing happened for ages. 

The BIOS I was trying to install is the same one that you stated in your reply. I was attempting to update the bios from a very old EFI version that shipped with it years ago.