Identifying the Position of the BIOS Chip on a Weird Motherboard (Help Please!)

Hi guys!

I’m restoring a barebones HP ProBook 455 G3 to life, but I’m having serious trouble with my BIOS chip on the motherboard. I’m used to dealing with bigger PCs, not things that small. :frowning: Anyway, I need to flash the BIOS.

But I have run into an embarrassing first. I can’t actually find the BIOS chip!

There are three candidates, and I know it’s definitely one of them, but two are devoid of text at all, and the other is so tiny that every magnifying glass I’ve used has failed to make it readable. I’ve looked everywhere for specs on this stock board to help me, and can’t find a thing. HP’s website is no help, even with serial number in hand. Customer support won’t help (even with specs!) because it is out of warranty. I have very technical specs now, but I still need an expert’s trained eye.

Images of the full motherboard and the section with the three chips zoomed in are attached below. In one image I’ve circled the three chips to make it clearer (my phone camera is not the best).

I imagine it is probably the chip next to the battery, but I don’t want to fry the board by making a mistake. All three have a dot indicating pin #1, so I couldn’t even use that as a process of elimination. :frowning: I’ve also been told (anecdotally) that some manufacturers make their laptops with two BIOS chips sometimes now, because it’s cheaper apparently. I’ve never built my systems that way, so I honestly wouldn’t even know how to proceed with flashing if there were two BIOS chips…

So, on to Problem #2:

EDIT: Nevermind, just going to use Linux.

Thanks in advance, and sorry for the long post. I’ve been tearing my hair a long time over this. Any advice is very appreciated.





HP Probook 455 G3 Quanta X73A DAX73AMB6E1

HP Probook 455 G3 Quanta X73A DAX73AMB6E1.jpg

That… is a lot more technical than I’m used to, though I think I understand it (forgive my stupidity if I’m wrong). But… oh no… does this mean I DO have two BIOS chips?

Do not know, it may concerns to UMA or DISC versions of same motherboard, start looking and u got to figured out the proper spi reading software version using the CH341, checking the dumps.
Do start always to get hold of a Schematic or BoardView files, yours here:
Good luck.

EDIT: I see… alien boards… built pre-installed system bios… i searched and couldn’t find it, yeah u should wait for a owner of such mboard that already worked in the spi to point u the right finger on it.

Thank you for the schematic. I thought I had looked everywhere, but just could not find it.

That being said, other than the first page or so, I understand very little, and I feel we’ve gotten way off topic from my original question. I’ve built many systems with pre-installed BIOS chips, and flashed those chips on Linux. My issue here is that I’m staring at a completely alien system board and I simply can’t tell which one is the BIOS chip.

I was directed here by my community of system builders who said this is where the BIOS experts were. I just need someone to point out the proper chip on the board. Please?

It’s not that I’m not willing to do the work. I’ve been working on this laptop very diligently for quite a while, and have money in its parts. I’m only asking for someone with the expertise to identify the BIOS chip to point it out to me. I can do the rest. I’ve flashed a BIOS before.

I apologize again for the long post. I am becoming so discouraged with all my work going nowhere, and struggling with the schematic has made me feel like an idiot.

EDIT: Also, in reply to your post, I can’t check the dumps if I can’t find the BIOS chip to use my reader to get the dumps. That’s my entire problem to begin with and why I made this post.


try this -…up_toolkit.html

see if it can dump the BIOS for you.

This looks like a fantastic tool, and one I definitely would have preferred over disassembly of the entire laptop. I have several complicating issues, however.

1 - The BIOS was bricked (sorta) when it’s last owner tried to upgrade it to a new version, so that’s why I need to flash it. It kinda works but not really.

2 - It came with no hard drive. I have a new one waiting for it, but I must get into the BIOS for it to see it’s there, and attempting to access any part of the BIOS or boot menu results in an instant restart of the laptop. (It will naturally go through several attempts via optical dive, USB, ect., as long as I leave it alone.)

3 - Somehow, even though the BIOS software has gone nutty, HP’s Secure Boot feature is still somehow active, preventing me from trying to boot from any unsigned source. I attempted many USB recovery tools to get a BIOS dump, but it rejected them for not being secure sources.

4 - I tried a Ubuntu installation flash drive with the hope of running it live, which is signed. Secure Boot did accept that as a signed source, but because the BIOS software is corrupted, it couldn’t actually boot anything up.

I feel re-energized after a good night’s sleep and ready to tackle the problem anew. I’m doing my best to wade through those specs, but still not really understanding where to find the chip. Perhaps it will still reveal the answers to me.

To close this topic out, I wanted to say that I got it! It took a while, and I think you guys were giving me some tough love… but it worked! That tough love made me hunker down and learn more about motherboards, resistors, ect, and how to read schematics more than I ever thought I’d learn…

You should have heard my shout of delight when my brain connected the info on the schematics you guys provided me (telling me that U18/U19 is where I’d find the BIOS chip), and the moment I found those magical labels on the motherboard with a magnifying glass. I cheered loud enough to wake up a roommate. Weeks of work vindicated!

Under a magnifying glass, the chip itself appeared to be physically damaged. The connections were oxidized, and one pin connection wasn’t even touching the board. I decided to try and flash the BIOS anyway, but my clip just wouldn’t stay attached to it. So I knew I would have to desolder the thing and do it that way.

So I got soldering equipment, watched a bunch of YouTube tutorials, and practiced on old, destroyed motherboards I had on hand until I was confident I had it right. Then I did the real job, and easily removed the chip. It was indeed mangled (not sure what happened to it), and wouldn’t even lock firmly into my CH341A reader. So I ordered a blank chip from Amazon (the schematics told me the exact chip I needed), flashed the BIOS on that, and soldered it back on the motherboard. I now have a fantastic laptop! (A preprogrammed BIOS chip for my model laptop off eBay was $20 plus shipping, while a lot of 5 blank chips off Amazon was $3, and would be here the next day free with Prime).

I set out just to flash a BIOS, and thanks to all of you, I’ve better learned how to read these complicated schematics, and also learned how to solder (and now the magical world of soldering is calling to me)! And I have my laptop finally, too.

Thank you, everyone. :grinning: