[Problem] Lenovo Tiny M910q not posting


So, I got a 2nd hand Lenovo Tiny M910q for cheap but once I got to the bios I saw that the administrator password was set, I could not change boot order and the only boot device was the NVME drive (which I didn’t have any at hand to test). Long story short: I cleared the CMOS and managed to go in the BIOS once, checked everything and turned the thing off to look for an usb-stick to boot. Then, no boot, no post, no beep, fan running, black screen. Out of nowhere. I imagine that something went wrong and corrupted the bios.

Now, I want to try to revive the thing with the CH341a. Ordered one and waiting to have it delivered. Meanwhile I am reading more than I ever wanted to know about BIOS and Hex Editors. But of course, I do not have a very clear understanding of some of the concepts, so I will ask the questions here and maybe someone can help clarify them:

- I have 2 chips on the board that “look” like a bios chip, the W25Q128JVSQ and the MXIC25L2006E. I understand that the Winbond is the BIOS as it has 16MB of storage, whereas the second has only 2MB. But I read about ME and BIOS chips being separated. Which should I look into?
- I can download the bios update from the Lenovo Website. I can open the .bin file on an Hex Editor, and I even try opening on the UEFITool. The codes used make no sense to me. Can I simply take this bin and write to the chip?
- If I can just write it (I will do 2 backups before, dont worry :), I don’t know HOW to update the Mac Address (I have on the sticker), the UUID, Board S/N and Windows License Key (which I do not have anywhere written down).
- I read on some places that before copying the .bin, I should “extract” some regions from the file into a separated file and then write this one instead. How do I know which region should I use?
- I also read that I should use a .bin file from someone else’s backup (I found one .bin in this forum somewhere). What should be the difference between Lenovo’s .bin file and one from a backup from some random person on the internet?
I am using the definition of .bin very loosely here, as I understood, the extension is meaningless and all the .bin, .rom, etc are the same thing, a binary file that contains executable for bios as well as configuration
- I know what is ME and BIOS (I use Intel ME/vPro at home sometimes) Is the “ME” section part of this BIOS file or is this in the other chip?

Finally, I am trying to create a checklist of what I want to do:
- Backup the current (assumed corrupted) BIOS.
- Try to find the UUID, S/N, MAC, Windows Lickey from that file (which tool should I use for search it?)
- Figure out how what to write to chip to have at least an initial boot/post working
- If I at least get a POST, I will try to write back the IDs to the .bin file (is this how it is done? merging this data back in the .bin?) and try not to mess up the working system
- profit! (i.e, avoid throwing away a perfectly nice computer)

Thank you for reading all of this, I tried to read more about the subject, but sometimes there are contradicting information around that may be due to manufacturer, technology, and other factors.
I am really trying to bring this board back alive without having to solder another chip there (I could’ve just bought another chip already programmed, but I hope that with the clamp I wont need to mess with soldering irons)

Thanks again!

Edit by Fernando: thread title shortened and customized

Should be enough with a single 16MB chip. 920q has 16 + 8 MB, but 910q has just a 8MB bios region. You can’t flash the bios update from Lenovo, it’s just a bios region. Best way would be look into the bios, find out what happened and decide after that. Writing back machine specific data into a stock bios is difficult if you don’t have manufacturers tools.