Banding Fix for 27" iMac

Discussion in 'Windows, Linux & Others on the Mac' started by urbanmacUser, Jan 20, 2010.

  1. urbanmacUser macrumors regular


    Sep 9, 2008
    I posted this in another thread but thought so many are having issues it deserved a thread of its own.

    This worked for me.
    I removed all the ATI drivers.
    The screen went balck and then went to 800x600 in the middle of the 27" screen :eek:

    I ran the BootCamp_3.1_64-bit installer again and it asked me to restart.
    On restart the screen was still 800x600 but stretched to fill the 27" screen.
    I logged in I was told drivers had been installed and to restart again.
    I restarted and when it came back banding had gone :D

    Driver Date is now: 23/09/2009
    Driver version: 8.661.0.0
  2. urbanmacUser thread starter macrumors regular


    Sep 9, 2008
  3. spcdust macrumors 6502a


    May 6, 2008
    London, UK
    I can vouch that this driver version does solve the banding issue. In my case I had this driver already installed on my iMac before I updated to Boot Camp 3.1. Installing Boot Camp 3.1 seemed to "update" the ATI driver to 8.681 (or something like that) and the banding became apparent - as I previously had the 8.661 installed I was able to go into the drivers properties and roll back to this version and get rid of banding.
  4. larzy macrumors regular


    Nov 16, 2008
    I too had this problem - I wish I didn't install the 3.1 update - oh well.

    But I was able to revert back to a previous driver... but I still think there are some "banding" or gradient that I didn't see before on the standard Win7 wallpaper :-(
  5. bamtan macrumors newbie

    May 16, 2009
    Just note that while this driver is clearly superior, it has its own problem:

    The screen will display the top half on the bottom vice versa and sometimes. It usually happens when booting in, or exiting a game, 5% of the time or so. To fix it just alter your resolution and then change it back, should be fine afterwards.

    Better than having colour banding anyway.
  6. mrjoshzombie macrumors newbie

    Jan 19, 2010
    Another way you can fix it, is after you do the 3.1 upgrade, simple going into your devices, and instead of uninstalling the driver, you can revert it back to the previously installed one. I know a few have already mentioned it, but I wanted to confirm it's the route I took as well. No need for a reinstall either and I haven't had a problem in about 12 hours now.
  7. TDHXXX macrumors regular

    Jul 3, 2009
    Where is this option? I cannot find it.
  8. MrCyberdude macrumors newbie

    Mar 5, 2009
    I will Guess for Win7 that it's under
    look for
    ATI Radeon HD 4850
    goto DRIVER Tab
    look for

    Should be the same for other versions of Windows.
  9. khan95osu macrumors newbie

    Mar 27, 2010
    Thanks for the help. The rollback method worked just fine for me.
  10. gutch macrumors newbie

    Mar 27, 2010
  11. MrCyberdude macrumors newbie

    Mar 5, 2009
    Sorry, I forgot about this thread. I replied here

    TIP: Dealing with Boot Camp and Windows 7 16-bit color problem | Top of Page | Tuesday, March 16, 2010

    MrCyberdude wrote to report a video problem with Windows 7 in Boot Camp, and shared his workaround:

    I found that Windows 7 in Boot Camp 3.1 changes the iMac 27" screen to 16-bit color, even when 32-bit is selected. This can be seen as a halo effect across the screen. Interestingly enough, the 2nd connected monitor is not affected. This can be demonstrated nicely by dragging a picture back and forth from screen to screen.

    The latest ATI Catalyst driver 10.2 does not fix this. But if you manually upgrade the graphic card driver in Device Manager and point it to the Boot Camp 3.0 ATI folder, all looks good again. I have not had any noticeable issues thus far.

    What I'm talking about doing here is basically a Manual Forced Driver installation.

Share This Page