an acquaintance of mine had trouble with his laptop so I decided to help him to fix it. I went down the rabbit hole and flashed a modded BIOS of the same laptop model into his laptop.
Playing around with the unlocked BIOS menu, I bricked the laptop. Luckily, I found in the internet an original ‘BIOS’ .bin file (size: 3072kb) of an internet user that they uploaded to a forum years ago. Using the dump file, I found the recovery BIOS file name and successfully utilized the USB flash method and made it work again.
The fun hasn’t been stopped yet. I continued to flash the modded BIOS and to try many settings in BIOS menu and to brick it, and to flash again and again. Then I found that USB-flashing the original BIOS .bin file, then upgrading with the modded version took me too long, I instead decided to flash the .bin file I found in modded folder. I bricked it again, but now the USB flashing method stops working.
Now the only last resort is reprogramming the BIOS chip with external hardware. So I bought the CH341A kit and got to dump the (corrupted) BIOS dump. But now I get into a new issue. The chip memory size is 8Mb. So is the BIOS/EEPROM dump. But the .bin file above is only ~3Mb big. How do I convert the .bin file to the dump file? How do I make it work?
I also assume (not certainly) that in the BIOS dump (the whole EEPROM region), other regions than BIOS region have been damaged somehow (due to the fact that I couldn’t USB flash again with the original .bin file). So how do I fix this without having an original EEPROM dump?
Thanks in advance.
In attach are the original .bin file (3Mb), the BIOS/EEPROM dump file (8Mb).
Thansk for the feedback. System specific info is in 2nd padding, 1st padding is unclear to me, looks like a smaller firmware? (EC / KB?), otherwise there’s a little information around bios version, but I suppose that’s static/ not board specific.
Mac is harder to recognize if you don’t know it or had the same bios before with known MAC to identify location.
Do you have the old MAC from a sticker? What does the OS show now?
One might try to recover the old bios. But since it’s unclear what happened and since there were small differences in the PreEfi part, too, and your board specific info seems to be complete, I’m pretty sure it’s not worth it.
Yeah, I think it won’t be worth the trouble. For WLAN/Wifi, it still registers the same old MAC to my router. But do you think the OEM key for the OS was erased or still there?
Also, I’m really curious how did you do to the bricked BIOS dump. I tried to replace the BIOS region with the original one, but failed. Guess I had to change some pointers somewhere, but for that I completely know nothing about.
It’s just the stock bios and the 2 original paddings before and after the first ‘volume’ in bios region. NVRAM is second last volume here, empty in stock, and this will be filles automatically again, normally. Didn’t see any Windows license information, but there are several tools which can check a (running) bios for license information.