Comment 8 for bug 775089

Hi Ave,
            I'm not 100% familiar with the ATI drivers as I have alway had a nvidia card myself, but my suspicion is this is something to do with the KMS (Kernal Mode Setting). I believe KMS is only implemented in the open source ATI drivers but you have said the proprietary Catalyt drivers have the same issue so maybe they do implement KMS. Another reason I suspect this may be the case is you said you could get around this before 9.10 which is when KMS was first supported for the ATI driver.

Can you try disabling KMS an see if that makes a difference? See: https://wiki.ubuntu.com/X/KernelModeSetting not sure if the settings on that page are still valid for turning it off or not so you may need to do more research if that doesn't work.

If that works then we can try reassign this bug to the right project. Good luck.

FYI anyone reading this: Kernel mode-setting (KMS) shifts responsibility for selecting and setting up the graphics mode from X.org to the kernel. When X.org is started, it then detects and uses the mode without any further mode changes. This promises to make booting faster, more graphical, and less flickery.