Hi
Thank you for this usefull froum.
I unlocked my asus k43tk headen bios settings using your modded bios, and it performed perfectly. But then I tried to disable the week apu graphic, to use its more powerfull discrete HD7670m graphics card.
I think I carelessly changed the settings in the northbridge menu, and after saving and restarting I got a black screen. The fan and leds are working.
I removed the CMOS battery for 3 days to reset it but no success.
Are the bios configs stored in the same nonvlatile bios flash, or in the EC (embedded controller) flash (I downloaded my laptop board schematic, it has two separate spi flash memories for "system bios" and "ec" firmware).
I have also tried to recover the bios by copying bios file on a flash drive and holding ctrl+home while turning it on; but no success.
Any help is appriciated.
@K43tk - sorry I’ve missed your thread until now! I thought you just posted and then sent me a PM too, that;s why I sent you the wise-crack reply 
I never made you a mod BIOS, so unsure what you are referring to. Your issue is common, in 99.9% of laptops you cannot enabled/disable or switch main graphics, otherwise you get black screen and can’t see display to recover BIOS.
The only way to fix this is you can try hard clearing of CMOS, but that’s not always possible on laptops. This is stored in the BIOS not EC FW. Other than than you need flash programmer (CH341A + SOIC8 test clip with cable) or know the keystrokes needed to do a blind BIOS flash.
The system is running normally, you just can’t see the display because you disabled it. Sometimes you might get lucky and can see display output on external monitor, so connect one and check if your system has external monitor connectors.
Some laptops have a 2-3 key combo for BIOS recovery, google around for this and your model maybe you can find something that works.
BIOS must have a special name (AMIBOOT.BIN or AMIBOOT.ROM or K43TK.BIN) and be on the root of a FAT32 USB 2.0 drive, smaller is better 128MB-2Gb (partition down anything larger than that for best chances)
This recovery method only works on certain models.
This is what you need, you can purchase locally, or from other places that ship faster, this is just to give you idea and this is cheap slow way to get the items
https://www.ebay.com/itm/332735579991
https://www.ebay.com/itm/382486015977
Once you get these items, DO NOT Erase or Write to your chip until you’ve made a backup and sent to me to check, otherwise the backup may not be valid and if you erase before I say go ahead you will loose all your board specifics (Serial, UUID, LAN MAC ID and windows activation sometimes too)
Here is software - http://s000.tinyupload.com/index.php?fil…257455007472602
And here is guide
https://www.bios-mods.com/forum/Thread-G…341A-programmer << Same as one directly below, but with all images expanded/visible at once
[GUIDE] Flash BIOS with CH341A programmer
Dear expert,
Thank you very much for such a fast and complete reply.
I have downloaded the bios file with enabled advanced settings from here:
RE:Asus K43TK Help To Unlock BIOS
It is fully functional.
I forgott to say that I disassembled my laptop and found the two flash chips footprints on the MB. Only the EC flash has been installed on the board, and the system bios flash (connected to Hudson-m3) is empty. Hence the system bios and EC firmware should be located on the same EC flash.
Iwill try some other methods of recovery (other than Ctrl+home), and if not successful, reflashing the chip via programmer. I worry about keyboard, because its caps lock is not working, but it is apparent that holding Ctrl+home gives different behavior. So I think the keyboard has semi-functinality. Why does the keyboard behavior depends on the graphics settings?
Thanks for linking where the mod BIOS was, if you flashed with EZ Flash all is OK (you wont loose your serial, UUID, LAN MAC ID Etc)
There is no empty BIOS chip on the board. Sounds like your trying to dump it with something incompatible, try other software version or get above mentioned tools.
The 2MB or larger BIOS chip (16 or 32 in ID on chip) is the main BIOS, this would not be erased from changing to a bad setting. Thus, if you are already trying to read it with some flash programmer (hardware), then it’s not compatible or you need to use other software or software version or choose different ID
Be sure you dump all chip before you erase or write, and do not erase or write to any chip you think is already blank (it’s not!)
Dear friend,
Sorry for my false explanation: "the system bios flash (connected to Hudson-m3) is empty" I mean no flash chip is installed on the board. The MB schematic shows a 2MB flash memory for the EC BIOS (named U42) and another chip exactly with the same specs for the system BIOS (U28). I noticed that U28 is not mounted on the MB; there is nothing there to attach a programmer to dump its contents.
However, I searched the web and found some guids to recover the original BIOS, which I think they have some risk to do:
Someone has stated that if the BIOS is healthy and its checksum is not corrupted (independent of the settings I have changed), then the Ctrl+home never tends to recover the BIOS from a USB flash drive. Someone else suggests shorting the data pin of the BIOS flash chip to ground, which forces all output contents of the chip to be read as zero. This perhaps will cheat the system to persuade it to do a recovery. But the SPI flash data output will not be damaged in this way?