I have a laptop. As soon as I connect my external monitor via HDMI, dmesg provides the following error:
[drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 254 Raw EDID: ff ff ff ff ff ff ff ff 1a b3 45 07 01 01 01 01 21 11 01 03 80 2f 1e 82 2a ee 95 a3 54 4c 99 26 0f 50 54 a5 4b 00 95 0f 81 80 81 40 71 4f 95 00 b3 00 81 c0 01 01 21 39 90 30 62 1a 27 40 68 b0 36 00 da 28 11 00 00 1c 00 00 00 ff 00 59 45 33 4c 30 31 30 32 36 33 0a 20 20 00 00 00 fd 00 38 4b 1f 53 0f 00 0a 20 20 20 20 20 20 00 00 00 fc 00 58 32 32 57 2d 31 0a 20 20 20 20 20 20 00 53 i915 0000:00:02.0: HDMI-A-1: EDID block 0 invalid. When I connect the external monitor via VGA, it works fine. The external monitor also used to work fine via HDMI/DVI quite some time ago. xrandr has the following output (the external monitor in connected by VGA and also by HDMI/DVI): Screen 0: minimum 320 x 200, current 1600 x 900, maximum 8192 x 8192 LVDS1 connected 1600x900+0+0 (normal left inverted right x axis y axis) 382mm x 214mm 1600x900 60.0*+ 1440x900 59.9 1360x768 59.8 60.0 1152x864 60.0 1024x768 60.0 800x600 60.3 56.2 640x480 59.9 VGA1 connected (normal left inverted right x axis y axis) 1680x1050 60.0 + 1280x1024 75.0 60.0 1440x900 75.0 59.9 1280x960 60.0 1152x864 75.0 1280x720 60.0 1024x768 75.1 60.0 800x600 75.0 60.3 640x480 75.0 60.0 720x400 70.1 HDMI1 disconnected (normal left inverted right x axis y axis) DP1 disconnected (normal left inverted right x axis y axis) So I can't even active the monitor by HDMI (xrandr --output HDMI1 --auto hs no effect). As anyone found a workaround? -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xserver-xorg-video-ati in Ubuntu. https://bugs.launchpad.net/bugs/914437 Title: Second display not recognized anymore; "EDID checksum is invalid" Status in “xserver-xorg-video-ati” package in Ubuntu: Confirmed Bug description: After upgrading from Ubuntu 11.04 to 11.10, the second display is not recognized anymore. It's an amd64 system with a Radeon HD 5700 graphics card. The first display, a Samsung P2250, connected via DVI, is recognized flawlessly. The second display, a Sony SDM-S51, connected with a VGA cable and a VGA-to-DVI-converter, is not recognized anymore. dmesg is full of the following message: [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 254 ... radeon 0000:01:00.0: DVI-I-2: EDID block 0 invalid. [drm:radeon_dvi_detect] *ERROR* DVI-I-2: probed a monitor but no|invalid EDID I verified this bug on a completely new system (clean install, all updates). Also reported as #24752 on landscape.canonical.com (" Second display not recognized anymore"). Full error message: [ 24.032103] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 254 [ 24.032104] Raw EDID: [ 24.032106] <3>ff ff ff ff ff ff ff ff 4d d9 50 1e 01 01 01 01 ........M.P..... [ 24.032107] <3>01 0c 01 02 0e 1e 17 78 ea 7e a9 a0 58 4e 96 25 .......x.~..XN.% [ 24.032109] <3>1e 48 4c a1 08 00 01 01 01 01 01 01 01 01 01 01 .HL............. [ 24.032110] <3>01 01 01 01 01 01 64 19 00 40 41 00 26 30 18 88 ......d..@A.&0.. [ 24.032112] <3>36 00 30 e4 10 00 00 18 00 00 00 fd 00 30 41 1c 6.0..........0A. [ 24.032113] <3>3d 0a 00 0a 20 20 20 20 20 20 00 00 00 fc 00 53 =... .....S [ 24.032115] <3>44 4d 2d 53 35 31 0a 20 20 20 20 20 00 00 00 ff DM-S51. .... [ 24.032116] <3>00 34 35 32 37 39 35 35 0a 20 20 20 20 20 00 97 .4527955. .. ProblemType: Bug DistroRelease: Ubuntu 11.10 Package: xserver-xorg-video-radeon 1:6.14.99~git20110811.g93fc084-0ubuntu1 ProcVersionSignature: Ubuntu 3.0.0-14.23-generic 3.0.9 Uname: Linux 3.0.0-14-generic x86_64 .tmp.unity.support.test.0: ApportVersion: 1.23-0ubuntu4 Architecture: amd64 CompizPlugins: [core,bailer,detection,composite,opengl,compiztoolbox,decor,resize,move,mousepoll,gnomecompat,snap,vpswitch,regex,grid,place,imgpng,wall,session,unitymtgrabhandles,animation,expo,workarounds,ezoom,fade,scale,unityshell] CompositorRunning: compiz Date: Tue Jan 10 20:07:50 2012 DistUpgraded: Fresh install DistroCodename: oneiric DistroVariant: ubuntu ExtraDebuggingInterest: Yes, whatever it takes to get this fixed in Ubuntu GraphicsCard: ATI Technologies Inc Juniper [Radeon HD 5700 Series] [1002:68b8] (prog-if 00 [VGA controller]) Subsystem: ATI Technologies Inc Device [1002:e147] InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012) MachineType: System manufacturer System Product Name ProcEnviron: PATH=(custom, no hostname) LANG=en_US.UTF-8 SHELL=/bin/bash ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.0.0-14-generic root=UUID=e0b8bb68-56f0-4c33-befc-c54dae6338e6 ro quiet splash vt.handoff=7 SourcePackage: xserver-xorg-video-ati UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 01/07/2010 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 0602 dmi.board.asset.tag: To Be Filled By O.E.M. dmi.board.name: M4A785TD-V EVO dmi.board.vendor: ASUSTeK Computer INC. dmi.board.version: Rev X.0x dmi.chassis.asset.tag: Asset-1234567890 dmi.chassis.type: 3 dmi.chassis.vendor: Chassis Manufacture dmi.chassis.version: Chassis Version dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr0602:bd01/07/2010:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKComputerINC.:rnM4A785TD-VEVO:rvrRevX.0x:cvnChassisManufacture:ct3:cvrChassisVersion: dmi.product.name: System Product Name dmi.product.version: System Version dmi.sys.vendor: System manufacturer version.compiz: compiz 1:0.9.6+bzr20110929-0ubuntu6 version.ia32-libs: ia32-libs N/A version.libdrm2: libdrm2 2.4.26-1ubuntu1 version.libgl1-mesa-dri: libgl1-mesa-dri 7.11-0ubuntu3 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 7.11-0ubuntu3 version.xserver-xorg: xserver-xorg 1:7.6+7ubuntu7 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.6.0-1ubuntu13 version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20110811.g93fc084-0ubuntu1 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.15.901-1ubuntu2.1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20110411+8378443-1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+bug/914437/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp