<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [Regression]Multiple monitors via DP TB dock detection/resolution/layout failure after Skylake->Coffeelake upgrade" href="https://bugs.freedesktop.org/show_bug.cgi?id=111179#c11">Comment # 11</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [Regression]Multiple monitors via DP TB dock detection/resolution/layout failure after Skylake->Coffeelake upgrade" href="https://bugs.freedesktop.org/show_bug.cgi?id=111179">bug 111179</a> from <a class="email" href="mailto:arcadiy@ivanov.biz" title="Arcadiy Ivanov <arcadiy@ivanov.biz>"> Arcadiy Ivanov</a> <pre>Thanks for looking at this. Both Dell Precision 7510 (SKL) and Dell Precision 5540 (CFL) have the same TB capabilities, TB3 ***HBR2***. It's true, with HBR2 they don't support 2x4k@60Hz(**), but the point of filing this bug was somewhat different - there was a change in behavior in monitor detection and resolution/refresh rate setting. SKL was supporting 2x4k with auto-detection, which, given hardware limitations, means that it was settling on 2x4k@30Hz mode all by itself. When an upgrade was made to CFL, this auto-detection stopped working properly - as you can see it tried to configure 2x4K@60Hz and failed, without fallback to 2x4K@30Hz. The change in behavior cannot be blamed on changes in Xorg, xrandr etc - the entire SSD was moved. Dock is similarly blameless - it was the same dock. The only change was laptop hardware. Given that monitors could be detected and EDID was read the expected fallback should've been onto the 2x4K@30Hz on CFL same as on SKL. It wasn't. All firmware is up-to-date. ===== ** there is a way with WD19TB for 2x4k@60Hz with DP pass-through, but this wasn't the setup for this bug</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>