Easy Guide : How to Downgrade ASUS Bios for all UEFI Motherboards

This guide is fully tested on several motherboards (dram speed and cpu ratio are adjustable after downgrading)

Things you will need :

1- Bootable MS DOS USB stick.
2- Afudos Utility 4.xx (UEFI).


1- Make sure to download the the correct bios for your board Flashing your bios with the
    wrong bios version may lead to a dead board.

2- Interrupting the updating process may lead to a dead board.

3- Don't downgrade your bios unless you are having some serious problems with your

    current bios version.

4- if anything went wrong while flashing your bios then don't restart your computer unless you had a successful bios flash.

* Steps to Downgrade your Bios :

*if you are having a x79 OR Z77 board with Asus flash back support click here

3- Extract the files .
4- Run HP tool (run as administrator if you are using windows vista or later).

1- Choose your flash drive 
2- Choose Fat32
3- Check Create a Dos startup disk option.
4- Choose the extracted windows 98 system boot files Folder 
5- Press START . WARNING ! All files on that flash drive will be removed so make sure
    you backup all your data before formating.

5- NOW you have successfully made your MS-DOS Bootable flash drive.

6- GO TO ASUS website and download the bios version you want to downgrade to and also
   download any older bios Version  NOTE : we will flash the bios twice once with the
   older bios version using afudos utility and the second time with the newer bios version
   (which is the Bios version you want to downgrade to) using Asus BUPDATER.

SO for example , if you want to downgrade to 2303 then you will downgrade your bios to 2103 first using afudos and then upgrade to 2303 using bupdater ,you can skip that step if you want and downgrade directly to the version you want using afudos (BUT DO IT ON YOUR OWN RISK).

7- name the older bios version "First" and the newer one "Second

8- Now copy them to your flash drive.

9- Download AFUDOS 4.XX 

10- Extract the files.

11- Now goto amiflash/Aptio/AFUDOS and Extract AFUDOS.rar

12- Now Copy AFUDOS.EXE to your flash drive.

13- Download Asus BUPDATER

14- Extract the files 

15- And now copy BUPDATER to your flash drive.

14- Now your flash drive should be something similar to this.

15- Now Restart your Computer and Enter Bios Setup by pressing the Delete key from your
      keyboard .

16- Now change boot priority to boot from your flash drive .

17- Note (now we will flash the bios with the older bios version First.rom)
      type AFUDOS FIRST.ROM /P /B /N  

18 -  it may gives you an error message that says : PI Version in SYS ROM mismatched PI
        Version in  ROM File! Force update it may be destroy the System BIOS (DON'T panic
        it's okay just press " F ") then it will ask you to confirm your choice so press " Y "

19 - DON'T INTERRUPT THE PROCESS it will only take few seconds so be patient.

20 - AFTER it finishes Type BUPDATER /isecond.rom 

this Command will flash your bios with the newer bios version (the version you want to  downgrade to ) using asus bios utility.


     there are so many ways to reset CMOS one of the easiest is to push the reset CMOS
     BUTTON at the back of your case for 5 seconds (usually you will find it above the audio
     jack inputs) (CHECK you motherboad manuel) or CHECK this video Reset CMOS

22- now turn on your computer and restore defult BIOS settings and restart.  

23- and now you have successfuly downgraded your bios.

                                       Bios FlashBack Method

*How to downgrade bios on x79 and Z77 boards with Asus flash back support :

1- format your flash drive to fat32

2- download the bios version you want to downgrade to from asus website.

3- copy the .rom file to you flash drive

4- Rename the .rom file as follow
  • Model name                            Rename the file
  • P9X79 DELUXE                             P9X79D.ROM
  • P9X79 PRO                                     P9X79PRO.ROM             
  • P9X79                                              P9X79.ROM
  • SABERTOOTH X79                       SABERX79.ROM
  • Rampage IV Extreme                    R4E.ROM
  • Rampage IV Formula                     R4F.ROM
  • Rampage IV GENE                         R4G.ROM 
  • P9X79 WS                                        P9X79WS.ROM

5- now Plug the USB storage device to the white-colored USB2.0 port, then press
    the USB BIOS Flashback button/ROG Connect button for three seconds till the
    LED begins to blink, then release.

6- Wait till the LED stops blinking, indicating that BIOS flashing has been

                           JUST LET ME KNOW IF YOU NEED ANY HELP I would love to hear your feedback guys .

                                                Comment and SHARE ! :D


  1. To all the various gods I pray this method works! I've spent 20+ hours trying to work out how to downgrade bios on my x79 sabertooth which bios v2002 has wrecked by hackintosh

  2. this method works for all uefi boards, please tell me if it worked for you and let me know if you need any help .

    1. I tried this method on my Asus Z9PE-D8 WS board..

      Must mention...

      The .ROM files became .CAP files following Rev 3109 starting @ Rev 3206..

      I currently have Rev 5003 installed and it crashed my system, I see only the 1st cpu and 1/2 the memory, I upgraded from Rev 3506,which worked perfectly and this killed it..

      I followed your instructions to the letter to create the bootable usb stick..

      The first command halts the process..

      afudos first.rom /p/b/n is followed by.....

      Reading Flash................Done

      30 - ERROR : Problem opening file for reading....

      Is it because the current bios file is .CAP and not .ROM ??

      Please help me, i'm losing my mind trying to restore this bios...


    2. The current bios file is write protected, is there a way around this problem ?

    3. I am trying to downgrade my ASUS M5A99FX PRO R2.0 but my BIOS format is a .CAP and not a .ROM do i need to change it?

    4. i donk know if you need this but here is the link to convert http://overclocking.guide/flash-back-older-bios-asus-z170/

  3. doesn't work for me..says "BIOS does not support AFUDOS"

    1. OOps..just needed a newer AFUdos

    2. if you are having a uefi motherboard then you should use AFUDOS (the one located in
      amiflash\aptio\afudos.zip\afudos.exe) not the one in amibios

    3. OK we have a big problem here. You said the correct afudos for UEFI bios is ver 4.xxx and then you said its the one in the aptio folder!! Well that one is ver 3.xxx. So which is correct I have an asus p8p67-m pro. I wont try this tell this gets an answer.

  4. See this for more information:


  5. Don't know if it matters, but BUPDATER is in v1.24 (your d/l link point to v1.22)


  6. both versions of bupdater have the exact same function (nothing to worry about)

  7. After press "F" to Force update, got "18 - ERROR: UANBLE TO STAR A SDECURE FLASH SESSION" ......

  8. what motherboard do you have ? , did you use afudos (the one located in aptio) ?

    1. Same same issue and I have an Asus sabertooth x79

    2. now guide updated to include X79 motherboards with flashback support .

    3. Hi, first of all thanks for your time, yesterday I tried for 1 hour, but honestly I can not dowgrade my MB (Sabertooth X79), when plug the USB storage in white-colored USB2.0 port, I press the USB BIOS Flashback button, LED of USB blink for 1 second, LED of button STAYS ON.....and ends there.... you can also wait 20-30 minutes, does not downgrade.

    4. Yes, I followed all the guide.

    5. sorry my mistake for sabertooth x79 boards you should rename the file to
      SABERX79.ROM not R4E.ROM , asus says that x79 and z77 boards are downgradable all you need to is to simply flash your bios using the same instruction (as upgrading bios) no tricks needed and sorry for the late response .

  9. This method did not work for me while trying to downgrade from 3207 to 2103 on a P8P67 Deluxe board. I followed the guide exactly, except I did not get an error while flashing first.rom (3207) with afudos. It wasn't until step 20 that I got stuck.
    I loaded bupdater, it auto-checked my file, which was second.rom (2103), then the following message popped up:
    "The BIOS file is older than the current BIOS"
    ...yeah, obviously.
    If I press any key, it takes me back to DOS screen. I can't move forward :|

  10. then what version did you downgrade to using afudos ? bupdater will tell you your current bios version and the bios version you want to upgrade to ? if it's newer
    then you probably mixed the files and downgraded to 2103 using afudos instead if so then repeat the process and make sure you downgrade to the older bios version using afudos and to the newer one using bupdater

    1. You're right, the files were mixed. Thank you for the help. The instructions are still confusing though.

      In my case, I just wanted to downgrade from 3207 (a newer BIOS), to 2103 (an older BIOS), which I think a lot of people are going to do based on the page where I found the link to these instructions:


      However, Step 6 says the "newer" BIOS is the one we want to DOWNGRADE to. That part didn't make sense. If we're downgrading, we're always going to be using an older BIOS because that's the definition of downgrade. Therefore, the OLDER BIOS we want to DOWNGRADE to should be renamed First.rom.

      Step 20 doesn't make sense, because UPDATER is exactly that, we're updating the BIOS and making it newer, so how is that downgrading?

      Users in my situation who are simply downgrading from 3207 to an older BIOS should only need to download the older BIOS they want to downgrade to, name it First.rom, open it with afudos as in steps 17-19 and skip step 20.

      No need to download a newer second BIOS then use bupdater, because all that will do is undo steps 17-19, which defeats the purpose of a downgrade, would it not?

    2. sorry for confusion i meant that if you are downgrading to 2103 for example
      then you will downgrade your bios to 2001 (older bios version) first using afudos utility then upgrade your bios to 2302 (the newer bios version and the version you want to downgrade to )using bupdater and that's only to make sure the last bios flash was using Asus utility and to make sure that the process was 100% successful and there is no chance that we brick the board .

    3. Oh ok, no problem, thanks for clarifying.
      Luckily, I was able to just downgrade without bricking, which I was nervous about.
      Ignore what I said about skipping step 20. It worked for me, but it may not work for others. Stick to the original guide everyone.
      Either way, your method works and I'm really glad I read this. Thanks a lot for your help :)

  11. wow, works fine!

    THX just4

  12. I have p8p67pro 3.0 board Bios updated to v3207 which also upgraded the updated ME version to, if i downgrade to v2303 how will updated Me version affect anything-i want to downgrade because it has screwed up my hackintosh!

    thanks for a great guide


    1. the updated me version won't affect anything because it will be downgraded as well , actually i had the same problem on my p8p67 deluxe board and i managed to downgrade my bios to 2103 with no problems using this guide ,you can also use the modified bios versions if you want (to enable native speedstep and sleep on your hakintosh) you can download them from here : http://bios4asus.blogspot.com/

  13. thanks for your prompt reply, i will let you know how i progressed!

    thanks again


    1. worked ok. thank you much appreciated -been looking for a fix to downgrade for months.

      the only slight hickup was after entering AFUDOS FIRST.ROM /P /B /N and then entering f to force, the dos screen kept rolling down had to press return then y blindly and then return when the first update was complete to return to msdos prompt.
      i was using msdos 7.1 not sure what win98 version is?, this might be why i had a rolling screen.

      The Me version now just shows N//A so i do not know if me was downgraded or not but working ok thanks.

      if i wanted to upgrade in the future would this be a good idea or one to steer clear of?

      thanks again


    2. glad it worked for you , i suggest that you don't (upgrade\downgrade) your bios unless you are having some serious problems with your current bios version , but you can freely upgrade your bios if you want , aslo make sure to check tonymac first before upgrading to see if anyone is experiencing problems with that bios upgrade ,i also suggest that you use modified bios versions to prevent (kernal panics , enable speedstep and sleep natively) , 'ME' was also downgraded .

    3. thanks for your reply, i will keep your suggestions in mind!

      and thanks again for such a usefull post.


  14. my mb is P8P67 REV 3.0 (3301 and 3207 missing turbo ratio(http://www.overclock.net/t/1270792/))

    I want to downgrade from 3301 (a newer BIOS), to 2303 (an older BIOS)
    so the first bios must older than the second bios so first must be 2103
    use afudos to flash after that use BUPDATER update to 2303

    The instructions are still confusing though for me!!!

    2103 is first 2303 is second right?!

    I will try it tommorw night becasu today is out for business

  15. yeah that's right downgrade to 2103 first using afudos , then upgrade to 2303 using bupdater

  16. With this method you will loose your UUIDs(User Unique iDs)Like MAC address etc...

    You have to backp these UUID wih FD44Editor then inject them in the BIOS you want to downgrade to.
    Once done you can follow this guide.

    See here for detailed explanations:


  17. My mobo is Asus m4a88td v evo usb 3.Can your guide affects my mobo. I got error after seventeen method.

  18. How does it work for the C602 (Asus Z9PE-D8 WS mobo)? As C602 is an upgraded x79 then I should use the x79 process or is it the other way around?

  19. when i try using afudos, it says: 46 - Error: problem getting flash information

    got a M2R32-MVP MB

  20. Asus P8P67 EVO downgrade worked flawless with this method, thank you.

  21. How can I restore MAC address and other else after downgrade? I have to do anything before to downgrade?


  22. Hi,

    Sadly I can't get this to work on my Asus P8Z68-V.

    If I use AFUDOS version 3.04 I get the following error message "Bios doesn't support all rom flashing functions.

    If I use AFUDOS version 4.4 I get the following error message "Bios does not support AFU"

    Any suggestions?

    1. Same here, AFUDOS says "...does not support AFU" MoBo Asus P8P67

    2. OK, did a mistake! All I had to do is to use AFUDOS from the APTIO-folder of course. ;-) Now I successfully downgraded from 3602 to 1704 and 2600k runs stable on 4,5 GHz again ^^

      Thanks very much for this guide with all the needed file links :D

  23. is there a solution?

    i've got same things than previous post:

    AFUDOS version 3.04 = Bios doesn't support all rom flashing functions

    AFUDOS version 4.4 I = Bios does not support AFU


    1. This comment has been removed by the author.

    2. ASUS Bios Recovery Tech Support
      call helpline number

  24. Works for me, successfully downgraded from 3402 to 1101 on a P8Z68-V PRO

  25. This worked flawlessly for me:Motherboard M5A99X EVO,thanks guys :)

  26. Thanks man! This worked fine on p8h67 (downgraded from 3608 to 1405)

  27. I have the same problem, and I have a P8P67 evo.
    "error - Bios does not support AFU"

    There are solutions?


    1. Mac Address and Board S/N are lost if you follow method described here!

      Instead, use FTK , English FAQ is here:

      French FAQ here:

      Original thread and D/L links (in Russian):

      Beginner guide to downgrade your BIOS:

      1- You must have configured Windows to always show file extension.
      2- Make a DOS bootable USB key (with Rufus http://rufus.akeo.ie/ )
      3- Put the content of FTK dos.zip on the root of the USB key.
      4- Put the bios file you want to downgrade to on the USB key and rename it bios.bin
      5- Boot on the USB key (change the hard drive boot priority in BIOS)
      6- Once in DOS, type reflash then hit Enter
      7- Once the flash is done, type poweroff and hit Enter.

      Enter BIOS (Del key) then reconfigure it.

      Downgrade in Windows is possible but not recommended.

  28. Thank you very much. Downgraded P8P67 from 3602 to 2103 and then 2302. Now I have stable 4.6GHz again with i7-2700K. With 3602 overclocking didn't work at all!

  29. I have a P8B75-M which did not boot Windows 8 properly with firmware version 1401. So I tried the downgrade suggested here.
    First I used AUFDOS to downgrade to 0812. No warnings, no errors or anything. Then:
    Update to 1001 with bupdater v.1.30. Again no warnings or errors just a "flash successful" message.
    Rebooted (but forgot to clear CMOS). Nothing, black screen, nothing happens.
    Cleared CMOS and tried booting again, but nothing happens.

    So I guess I'm stuck with a dead board, at least until I figure out how to program the chips using some kind of SPI programmer.

    Conclusion: Don't attempt this on P8B75-M boards (and probably it's siblings as well)

  30. I tried this method on my Asus Z9PE-D8 WS board..

    Must mention...

    The .ROM files became .CAP files following Rev 3109 starting @ Rev 3206..

    I currently have Rev 5003 installed and it crashed my system, I see only the 1st cpu and 1/2 the memory, I upgraded from Rev 3506,which worked perfectly and this killed it..

    I followed your instructions to the letter to create the bootable usb stick..

    The first command halts the process..

    afudos first.rom /p/b/n is followed by.....

    Reading Flash................Done

    30 - ERROR : Problem opening file for reading....

    Is it because the current bios file is .CAP and not .ROM ??

    Please help me, i'm losing my mind trying to restore this bios...

    The current bios file is write protected, is there a way around this problem ?
    The bios chip itself is WINDBOND 25X64 Series.. 8 pin.

    Write Protect (/WP) Pin 3....From Windbond datasheet..
    The Write Protect (/WP) pin can be used to prevent the Status Register from being written. Used in conjunction with the Status Register’s Block Protect (BP2, BP1, and BP0) bits and Status Register Protect (SRP) bit, a portion or the entire memory array can be hardware protected. The /WP pin is active low.

  31. Tks so much dude... Works perfectly on the ASUS P8H61-M PRO. Hail from Brazil

  32. This worked on the F2A85-M LE board without any problems. Did not get a warning message.

    Use the 3.xx version from AFUDOS.

  33. This looks very promising. However, I just prepped a usb stick following all of your steps but the only difference is that the files are *.cap and not *.rom. Will this be a problem or should it work? I haven't tried yet and here's why:

    My cpu is running fine. However, I noticed there is an update for the BIOS. I am very meticulous and from what I've read you shouldn't update if it isn't broken. I noticed the newest update makes for better compatibility with some pcie devices. I'm planning on buying a new gpu which will utilize a new pcie slot. I don't want to be stuck so I'm planning ahead that if I were to update bios if needed that I have a back up plan to restore my computer to it's current fine working condition if need be. Any feedback is appreciated!

  34. thank very much, i have updated my bios (asus p8p67-m) and now cant open windows. computer starts with warning about psu, core voltages, cpu temperature. it says cpu is 255 C motherboard is -125 C and fan speeds are at max. 65555 rpm. Now i will try downgrade, i hope it will work.

  35. THANKS!!!!!!!! the ASUS tec told me I had to buy a new bios ROM chip and this saved me money and time. It works with newer systems too. I have a Z9PA-D8

  36. I LOVE YOU, works perfect

  37. I get 3-Error ROM file size does not match existing BIOS size. Am I supposed to leave the roms in their zipped form?

  38. Any way to downgrade uefi bios on graphics card back to non uefi? Asus card

  39. 3-Error ROM file size does not match existing BIOS size.

    Does someone knows what happened guys ? I get this this error and its not working anymore.

  40. This method works on my ASUS P8H61-M LE R2.0 Motherboard.

    The key is to use RIGHT AFUDOS version. I am using AFUDOS 5.0.5. Downloaded from AMI website:


    Use the one under \aptioV folder.

    Thank you for posting this great method.

    Victor Wang

  41. Does this method work on a z87-c board?? i currently updated my bios from 1801 to 2103 but that version is crap! the full turbo mode disappeared.. i want back to 1801! the usb flasback is no option cause i can't find any button on the back of the case..

  42. My GPU led off and not the video does not work.
    You can contact me by email, maycon.mflima@gmail.com
    Really need to know what you did.

  43. Esse método funcionou perfeitamente para mim, a minha sabertooth p67 rev b3 estava no release de bios 3602, o último disponível no site da asus, me arrependo arduamente de ter atualizado pois ela estava anteriormente na versão 1502, depois de colocar no último release não consegui usar o asus my logo assim como o hackintosh de moutain lion.

    Me deixa tentar explicar como consegui:

    Baixe o AFUDOS no site da American Megatrends "http://www.ami.com/download-license-agreement/?DownloadFile=AMIBIOS_and_Aptio_AMI_Firmware_Update_Utility.zip", o AFUDOS que usei foi o que esta dentro da aptio e nao o que está na pasta aptioV, coloque o afudos no pendrive de boot assim como esta no passo-a-passo deste site.

    Eu queria fazer o downgrade para a versão de BIOS 2302.

    Assim como descrito nesse site baixei a 2302 do site da ASUS e uma versão anterior a 2103 "http://www.asus.com/br/Motherboards/SABERTOOTH_P67/HelpDesk_Download/", só que ao baixar do site da ASUS me deparei com um problema, pois as BIOS vem com um nome muito longo, por exemplo "SABERTOOTH-P67-ASUS-2103.ROM" e o MS-DOS 16 Bits que usamos para usar o AFUDOS e o BUPDATER só suporta arquivos com até 8 letras, poderiamos simplesmente renomear os arquivos só que se fizer isso o BUPDATER não consegue mais lelos (vi nos comentários que várias pessoas não conseguiram ler os arquivos BIOS), a saída foi usar um programa da asus chamado "Bios Renamer for USB BIOS Flashback and Crashfree BIOS 2" ele está disponível nas utilidades de bios na página de suporte da placa mãe "http://www.asus.com/br/Motherboards/SABERTOOTH_P67/HelpDesk_Download/", ele renomeia os arquivos de BIOS para um nome com menos de 8 caracteres e não corrompe o arquivo. Só que teve mais um problema, pois o Bios Renamer for USB BIOS Flashback and Crashfree BIOS 2 renomeia os arquivos sempre com o mesmo nome e não teria como por 2 arquivos no pendrive de boot com o mesmo nome, no pendrive de boot criei uma pasta chamada "BUP" (SEM ASPAS) e coloquei dentro o BUPDATER e o arquivo de BIOS que vou fazer o downgrade renomeado pelo "Bios Renamer for USB BIOS Flashback and Crashfree BIOS 2", o arquivo de BIOS que vai ser usado pelo AFUDOS ficou na raiz do pen drive de boot.

    Dentro do pendrive de boot vai ficar assim:





    Note que são 2 arquivos de BIOS com o mesmo nome, só que um está na raiz do pendrive de boot e o outro na pasta BUP.

    No passo-a-passo deste site você primeiro começa fazendo o flash da BIOS anterior a que você quer que seja o downgrade e depois faz o flash da BIOS em questão que voce queria.
    Depois de fazer o flash da BIOS anterior com o AFUDOS (comando: AFUDOS SABERP67.ROM / P / B / N) , vai gravar a bios anterior ao que voce deseja fazer downgrade de modo forcado e vai completar normalmente, ai voce precisa ir ate o diretório do BUPDATER para usa-lo digite CD C:\BUP dessa forma vai aparecer no prompt de comando C:\BUP> ai voce executa normalmente o comando para fazer o flash no BUPDATER, no meu caso aqui fiz BUPDATER /iSABERP67.ROM , após isso gravou a BIOS que eu queria normalmente, apertei o power do gabinete e dei clear cmos direto na placa mãe através do jumper, liguei novamente e deu tudo certo gracas a deus.

    * Só desligue se der tudo certo, caso contrário a placa pode morrer.

    Peco desculpas pelo comentário extenso, mas queria ter certeza de estar ajudando a quem ainda ficar com dúvidas, agradeço muito pelas dicas deste site salvou meu dia.

    Se ficar inseguro quanto ao procedimento não hesite em me mandar um e-mail em "ali_santos@live.com" com asunto "downgrade bios asus", vou tentar ajudar como puder.

  44. I have a question, i am trying to downgrade my M5A99FX PRO R2.0 From the latest bios version which is 2501 to 1101. Why? Because ever since i updated bios i started to get random bluescreen with my overclock settings and its starting to get realy annoying because the motherboard is unstable. Now the BIOS fileformat is a .CAP and not a .ROM , would that matter? when i boot the DOS flashstick and write AFUDOS FIRST.CAP /P /B /N instead of AFUDOS FIRST.ROM /P /B /N would it work?

  45. I have a Z9PE-D8 WS motherboard and I am trying to downgrade from 5701 to 3206. I tried this sequence but received an error that the file was write-protected. Any help you could provide would be great. Thanks

  46. Would this work on a P7H57D-V EVO? I have a 19xx BIOS version, and i'm wanting to downgrade to version 1606, possibly lower for overclocking purposes.

  47. hi there, you are giving me hope again^^, i maxed my bios on sabretooth z77, i checked your solution, but cant find the model for my motherboard and what to rename the file to......, does this still work? i really hope so^^

  48. This comment has been removed by the author.

  49. i have a problems with the install driver chipset, of my p8p67 deluxe, return version of my bios, is the solution of my problem?

  50. i got asus x55vd laptop and d bios update was fail. my laptops is dead now how can i get back to work. help is appreciated ..