Screen shakes fixes

Many of 4850 experience screen shakes with osx driver. Now, thanks to Majito,  we discovered why it happens.

This happens because of memory clock downscaling in 2d mode.(from 993 to 750 in my case)

so, there is 3 possible solutions:

1) Disable pwoerplay at all, here is pkg with natit which will do so

Natit no powerplay

Install it after installing pkg with drivers from irc

2) Edit bios to make mem clocks in 2d mode to match mem clocks in 3d mode, it’s a bit dangerous and not recomended  info about it can be found here Insanelymac thread

3) This way is only for 4850 atm. OSX drivers get information about clock speed from ATY,bin_image variable from ioregistry, normaly it has bios dump natit got from your card, but, we can replace this content with anything we want, so I put modified 4850 bios into natit and no shakes, i think powerplay is working for downscaling core clocks. You can get it here – Natit with 4850 bios inside , install it after installing driver pkg from irc. it’s like second case without actual flashing 🙂
The bios I used for it –4850 bios no shakes


  1. zillch
    March 1st, 2009 | 7:55 pm

    Hi netkas:

    My card is Powercolor HD4850 , it has 3 connectors: HDMI+Display Port+DVI(close to mobo). I only have a CRT Screen (NEC FE2111SB) , so after Driver pkg installation I tried DIV2VGA adapter in DVI port but just a black screen : (

    Question: as I know,HDMI2DVI+DVI2VGA solution could not have analog RGB signal needed by CRT , so how can i do to get this driver work ?

    sorry for my poor english~

  2. netkas
    March 1st, 2009 | 9:26 pm

    try hdmi2dvi+dvi2vga without cable and dvi2vga conencted to ur monitor.

  3. jeo
    March 1st, 2009 | 9:50 pm

    Hi netkas,

    Do you know if Radeon 4850 fan fix can be applied in OS X? I’m worried about overheating my card…

    Thanks for all your hard work! My hackintosh is working great thanks to you…


  4. ago
    March 1st, 2009 | 9:58 pm

    first solution works for me on my saphhire radeon 4850

  5. zillch
    March 1st, 2009 | 11:34 pm

    thanks netkas, i’ll try and report to you…

  6. rimkashox
    March 2nd, 2009 | 5:49 am

    Netkas, You’re a GENIOUS!!! It’s all I have to say… Thank god we have people like u in the community 🙂

  7. zillch
    March 2nd, 2009 | 5:55 am


    I tried with my card, HDMI2DIV+DVI2VGA @HDMI port and another DVI2VGA adapter @DVI port ,boot with -F -X -V

    The result is :Still BLACK SCREEN after a blue screen flashed past. : (

    seems on this beta driver, the DVI port(close to mobo) have not any analog RGB signal output : (

    any ideas?

  8. netkas
    March 2nd, 2009 | 10:42 am

    wait till new 10.5.7 betas with better FB driver

  9. March 2nd, 2009 | 9:06 pm

    Any word on people who keep getting a black screen when changing resolutions?

  10. March 3rd, 2009 | 2:50 pm

    haha:), 4870 appears in Apple Store:

    MB999LL/A – ATI RADEON HD 4870 512MB

  11. s3dose
    March 7th, 2009 | 8:25 am

    Hey netkas!

    First, thanks for your effort.
    I have problems installing the Natit_with_4850_bios_inside.pkg. During reboot my machine stops at the splash-screen, which suddenly turns into grey. The same occurs with the package that disables powerplay at all.
    Any suggestions?

  12. Jared
    March 9th, 2009 | 9:28 pm

    hey netkas! thanks for all of your work. i was able to install iPC OSX 10.5.6 on a intel core 2 duo, but now i got an i7/gigabyte ud5 machine with ocz 6gb 1600 tri-channel and radeon 4850, and it won’t boot. it shows the gray apple screen for a split second but then restarts every time. do you have any idea what might be the problem? the bios settings are correct to my knowledge (AHCI). thanks a ton!

  13. Avakov
    March 9th, 2009 | 10:53 pm

    Sorry, I’m Russian and I don’t understand details…
    1) Where I can download driver?
    2) I need to update Natit?
    a) How to update Natit?
    b) Where I can find new version of Natit?
    I have 4850.
    Thx, Avakov.

  14. Pimpa
    March 11th, 2009 | 4:39 pm

    Hi netkas!

    I’ve tried the 1st release of the beta drivers with my Sapphire 4850 Toxic, but I had kernel panic upon restart, sleep, shutdown. After I have tried this Natit with a bios included (and endited) and voiala: kernel panics gone! 🙂
    I’ve read in the other topic that dual DVI working in some cases and I had give a try too…

    1st: if I boot with two monitors (DVI) connected: fail! (blue screen on both…)
    2nd: if I boot with DVI2VGA in the first and DVI (monitor) in the second and after the system is running plug a DVI cable into the 1st port (replacing DVI2VGA) : screen flashing and everything seems OK, but after few seconds the system freezes 🙁

    I’d like to try with other bioses but I don’t know how to encode the binary data into the plist, so if U can help me it would be great.

  15. sekil
    March 11th, 2009 | 9:00 pm

    to avakov
    Привет 🙂
    Драйвера качать
    Natit отсюда
    Сначала ставишь дрова потом natit

  16. lun_IX
    March 13th, 2009 | 1:21 pm


    Bootoption “cpus=1” should do the trick. At least it did for me (Dell XPS Studio Core i7).

  17. March 14th, 2009 | 5:22 am

    Works for me. I updated this and it works great. The resolution isn’t perfect, but I will deal.

  18. Aridif
    March 14th, 2009 | 3:37 pm

    Hi, how do I install these kexts to EFI-partition, I have copied all 6 (the new natit with bios) and run the update script, but when i reboot, the scree is black. (p5q pro, 4850 (flashed – no powerplay – working)

    Thanks, Aridif

  19. almostthere
    March 18th, 2009 | 5:02 pm

    Hi ! Netkas
    first i have to sorry for my bad english
    i follow the instruction
    install 4850 driver then shutdown my ideneb1.4
    then i plug the dvi2vga adapter to another port of dvi
    and turn the computer on
    do i miss some step?

    my result is ,,there is no signal after the blue flash on screen

    i dont know how to do,,,,please advice, me thank you

  20. Andy
    March 20th, 2009 | 3:47 pm

    I’m on a dell e1705, I’m running 10.5.6, everything is great except the video. With an ATI 1400M, I have 2 options at the moment (after trying every kext known to man)

    a) Screen tearing without Natit (QE works fine)
    b) run diobolik’s 1300 driver and have screen shakes like crazy (with no mouse tearing)

    What I don’t understand is why with Natit I don’t get mouse tearing and with it I get screen shakes. From what I understand Natit is using the same ATIRadeonX1000.kext that I get with the tearing.

    Any help you guys can give would be greatly appretiated.

  21. Andy
    March 20th, 2009 | 5:26 pm

    NVM got it working. Basically I have to manually switch to the external monitor while OSX is booting, before it gets to the log in screen and the flicker goes away o.O whatever lol I can live with that.

  22. manusito
    March 26th, 2009 | 4:30 pm

    natit with bios included working great here!! thaaaanks a lot!!!

  23. Dagor
    April 16th, 2009 | 11:59 pm

    So this patch adjusts the 2D Mhz to the one running in 3D Mode? Does that mean the Card uses the Power and produces the heat it would use in 3D Mode all the time?

  24. netkas
    April 17th, 2009 | 7:42 am

    kexts cant be instaleld to efi partition

    Dagot, natit with bios, it does noy drop clocks only for memory , so, in 3d clocks is 625/1000, in 2d mode clocks is 500/1000

  25. Lalu
    December 2nd, 2009 | 9:54 am

    Man… thanks a ton. This is some awesome stuff that you do. Helped me a lot, really. Now my purpose of running Final Cut is accomplished after a week of trying continuously to install OS X, reinstalling it, messing up with it and ruining it, I finally made it after reading this post. Thank you very much and greetings from Romania.

  26. June 22nd, 2010 | 12:05 pm

    […] отмечали некоторые товарищи и даже netkas отметил это у себя, но у меня Natit не поднимал видеокарту и всё тут. ATY_Init […]

  27. Buhmi
    November 3rd, 2010 | 8:28 am

    Hey netkas,

    could you upload the Natit_with_4850_bios_inside.pkg again? Rapidshare has deleted it >.<

    thanks a lot,


Leave a reply