https://bugs.freedesktop.org/show_bug.cgi?id=81476
--- Comment #20 from Alex Deucher <agd5f at yahoo.com> --- (In reply to comment #19) > > I'd believe it as a hardware limitation if inverting the first two monitors > didn't fix it. If I were willing to physically turn my first two monitors > upside-down, it would work fine with the given hardware. The hardware can > display across my three monitors at 4800x1200 as long as two of the screens > are inverted. We just need to make the software put those screens into the > hardware the other way up! As I said before, it only works with rotation because it's scanning out of different buffers when rotation is enabled. When you enable rotation a shadow buffer is created which is a rotated duplicate of the sub-region of the entire desktop. So for the rotated case, the display hw is scanning out of a 1600x1200 surface rather than the full 4800x1200 surface. If you wanted to you could do something similar for the non-rotated case in the xserver, but that would incur an extra copy for every update of the desktop in the non-rotated case. If you want to test further, try and disable acceleration (Option "NoAccel" "true" in the device section of your xorg.conf) or use the modesetting driver (xf86-video-modesetting). You won't be able to use rotation since that requires acceleration do to the rotated blit, but that will take all non-display hw factors (3D, etc.) out of the equation. -- You are receiving this mail because: You are the assignee for the bug. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.freedesktop.org/archives/dri-devel/attachments/20140722/bc009dff/attachment.html>