Red Hat Bugzilla – Bug 624309
Kernel update breaks ATI dual monitor setup
Last modified: 2010-08-27 01:52:01 EDT
Description of problem:
Standard install of Fedora 13 x64. Fully updated (16 Aug 2010).
I have two LCD screens (Philips 19inch, 1280x1024, both with DVI connectors) attached to an ATI video card. The screens are set up as one big desktop (left and right). Using the default Fedora opensource ATI video driver.
When booting with kernel 126.96.36.199-147.2.4.fc13.x86_64, each screen now mirrors each other with a desktop that is sized to just one screen ie. the first screen shows a desktop that is 1280x1024, the second screen is a mirror of the first screen. Using 'Monitor Preferences' GUI shows only one screen available, even after pressing 'Detect monitors'.
When booting with the previous kernel 188.8.131.52-147.fc13.x86_64, one big desktop spread across the two screens works fine (and has done so since Fedora 13 first came out). 'Monitor Preferences' GUI shows two screen available for adjustment.
Version-Release number of selected component (if applicable):
Broken dual monitor support - 184.108.40.206-147.2.4.fc13.x86_64
Working dual monitor support - 220.127.116.11-147.fc13.x86_64 (and all previous F13 kernels).
[ 22.914] (--) PCI:*(0:1:0:0) 1002:944c:1043:0280 ATI Technologies Inc RV770 LE [Radeon HD 4800 Series] rev 0, Mem @ 0xd0000000/268435456, 0xe0200000/65536, I/O @ 0x00002000/256, BIOS @ 0x????????/131072
This was probably broken in -147.2.3 by drm-radeon-fix-shared-ddc-handling.patch and is fixed properly in 18.104.22.168 and 22.214.171.124 . Can you try 126.96.36.199-37 from the updates-testing repository?
I'm going to assume this is fixed in 188.8.131.52
kernel-184.108.40.206-149.fc13.x86_64 (from koji)
kernel-220.127.116.11-37.fc13.x86_64 (from updates-testing)
Both kernels fix this bug.
Thanks. Closing bug.
We'll let Bodhi close the bug when the kernel gets released.