<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [SKL] monitor is not detected unless it was active during boot" href="https://bugs.freedesktop.org/show_bug.cgi?id=97877#c4">Comment # 4</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [SKL] monitor is not detected unless it was active during boot" href="https://bugs.freedesktop.org/show_bug.cgi?id=97877">bug 97877</a> from <a class="email" href="mailto:madman2003@gmail.com" title="Maarten Maathuis <madman2003@gmail.com>"> Maarten Maathuis</a> <pre>An interesting observation is that when plug the monitor into another system which has an older nvidia card using nouveau (only HDMI is available, card is too old for displayport). It seems that the i2c connection is unreliable, sometimes more or less data is retrieved, but never all of it seems, and sometimes none. I wonder if there is some sensitivity to i2c speed. My general observation of these monitors is that they are slow to turn on on displayport (locking in a mode takes some time), but on hdmi it is faster, is there some kind of throttling going on the displayport side that is being ignored on the HDMI side? [768542.009520] [drm:drm_edid_block_valid [drm]] *ERROR* EDID checksum is invalid, remainder is 254 [768542.009561] Raw EDID: [768542.009575] 00 ff ff ff ff ff ff 00 4c 2d d0 0c 56 53 4d 30 [768542.009593] 20 19 01 03 80 34 1d 78 2a 12 55 a9 54 4d 9f 25 [768542.009610] 0c 50 54 bf ef 80 71 4f 81 00 81 c0 81 80 95 00 [768542.009626] a9 c0 b3 00 01 01 08 e8 00 30 f2 70 5a 80 b0 58 [768542.009642] 8a 00 09 25 21 00 00 1e 00 00 00 fd 00 18 4b 1e [768542.009658] 87 3c 00 0a 20 20 20 20 20 20 00 00 00 fc 00 55 [768542.009678] 32 34 45 38 35 30 0a 20 20 20 20 20 00 00 00 ff [768542.009694] 00 48 54 48 47 38 30 30 30 30 35 0a 20 20 07 ff [768542.010899] nouveau 0000:01:00.0: DRM: DDC responded, but no EDID for HDMI-A-1 [768578.474150] [drm:drm_edid_block_valid [drm]] *ERROR* EDID checksum is invalid, remainder is 157 [768578.474171] Raw EDID: [768578.474178] 00 ff ff ff ff ff ff 00 4c 2d d0 0c 56 53 4d 30 [768578.474187] 20 19 01 03 80 34 1d 78 2a 12 55 a9 54 4d 9f 25 [768578.474195] 0c 50 54 bf ef ff ff ff ff ff ff ff ff ff ff ff [768578.474202] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [768578.474210] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [768578.474218] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [768578.474225] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [768578.474233] ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [768578.475264] nouveau 0000:01:00.0: DRM: DDC responded, but no EDID for HDMI-A-1 [768590.904774] [drm:drm_edid_block_valid [drm]] *ERROR* EDID checksum is invalid, remainder is 181 [768590.904813] Raw EDID: [768590.904826] 00 ff ff ff ff ff ff 00 4c 2d d0 0c 56 53 4d 30 [768590.904843] 20 19 01 03 80 34 1d 78 2a 12 55 a9 54 4d 9f 25 [768590.904860] 0c 50 54 bf ef 80 71 4f 81 00 81 c0 81 80 95 00 [768590.904876] a9 c0 b3 00 01 01 08 e8 00 30 f2 70 5a 80 b0 58 [768590.904892] 8a 00 09 25 21 00 00 1e 00 00 00 fd 00 18 4b 1e [768590.904908] 87 3c 00 0a 20 20 20 20 20 20 00 00 00 fc 00 55 [768590.904924] 32 34 45 38 35 30 0a 20 20 20 20 20 00 00 00 ff [768590.904940] 00 48 54 48 47 38 30 30 30 30 35 0b ff ff ff ff [768590.906012] nouveau 0000:01:00.0: DRM: DDC responded, but no EDID for HDMI-A-1</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are on the CC list for the bug.</li> <li>You are the assignee for the bug.</li> </ul> </body> </html>