<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_RESOLVED bz_closed" title="RESOLVED NOTABUG - amdgpu cannot set 2560x1440@60 mode even though monitor,gpu and motherboard support it" href="https://bugs.freedesktop.org/show_bug.cgi?id=105534#c5">Comment # 5</a> on <a class="bz_bug_link bz_status_RESOLVED bz_closed" title="RESOLVED NOTABUG - amdgpu cannot set 2560x1440@60 mode even though monitor,gpu and motherboard support it" href="https://bugs.freedesktop.org/show_bug.cgi?id=105534">bug 105534</a> from <a class="email" href="mailto:alexdeucher@gmail.com" title="Alex Deucher <alexdeucher@gmail.com>"> Alex Deucher</a> <pre>(In reply to Christian König from <a href="show_bug.cgi?id=105534#c3">comment #3</a>) > What you can use is either an active DP to dual DVI converter (probably > rather expensive if such a thing even exists) or native DP/HDMI (if the > monitor has connectors for that). They are actually relatively common for just these sorts of scenarios. Not sure about cost however. (In reply to philipmorant from <a href="show_bug.cgi?id=105534#c4">comment #4</a>) > Thanks for replies. My monitor is DVI DL only. > > My old Haswell i5 4670 with HD4600 graphics was also single link DVI only > (<a href="https://communities.intel.com/thread/44135">https://communities.intel.com/thread/44135</a>), and it worked at 60Hz. Could > somebody please explain why haswell can do it but raven can't ? I'm not sure how the intel hw is designed. I can't comment on exactly what is happening. I suspect what is happening is that the intel driver is not validating the link requirements and treating the DVI port like HDMI and sending the high bandwidth mode over a single TMDS link. The monitor just happens to accept it. > > Otherwise I find myself assuming that the hardware is capable of DL DVI, > just that the manufacturers aren't validating for it, ergo fixable in > software. No. DL DVI requires two digital transmitters, one for each TMDS link. We only wire a single transmitter to each physical connector. For DL DVI, you need two transmitters connected to the physical connector. > > I understand if AMD object to coding for something that hasn't been > validated (I'd do the same myself). Would it be possible alternatively to > provide hints in log output or code comments or on a wiki somewhere, such > that people in my position can hack the source themselves ? You could try hacking the driver to treat the monitor as HDMI even through it's DL DVI. Maybe your monitor will accept the timing over a single TMDS link. > > Secondly, even accepting the single link limitation, shouldn't it be > possible to run at 33 refresh rate ? I tried at 30 and got nothing. > It depends on the hardware and the panel in the monitor. The monitor hardware may not like 30 Hz refresh rates. > Thirdly, why does amdgpu refer to the connection as HDMI-A-3 ? There's no > HDMI in the setup at all. The display connectors are read from a table in the bios and are determined by the OEM that designs the board. It our case the OEM seems to have set it up as 3 HDMI connectors and a DP connector. What physical connectors are actually on the board?</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> </ul> </body> </html>