9 Replies Latest reply on Jul 13, 2016 3:11 AM by oskaremil

    Displayport monitor not detected at startup

    christes

      I'm currently running a triple monitor setup with two 1080p monitors using DVI and a 1440p monitor using Displayport.

       

      Frequently, the Displayport monitor will not be detected when I start Windows.  It will show all of the startup / POST stuff perfectly fine before that, however.  But as soon as it gets to Windows, it tells me that there is no signal.

       

      Physically disconnecting and reconnecting the monitor to the video card causes it to be detected and mostly work like normal.

       

      This has been happening for a couple weeks.

       

      • AMD Graphics Card
        • R9 280 / HD 7950 crossfire
      • Operating System
        • Windows 10 64 bit
      • Driver version installed
        • 16.6.1 (Does not occur on 16.3.2)
      • Display Devices
        • Acer K272HUL (DP)
        • Acer AL2416W (DVI)
        • Acer B243W (DVI)
      • Motherboard
        • ASUS P6T
      • CPU/APU
        • Intel X5675
      • Power Supply Unit  Make, Model & Wattage
        • XFX 750W PRO
      • RAM
        • 12GB
        • Re: Displayport monitor not detected at startup
          amdmatt

          Please provide more information so we can try to help.

          INFORMATION REQUIRED WHEN POSTING A QUESTION

            • Re: Displayport monitor not detected at startup
              christes

              I've updated the original post.

               

              It worth noting that this does not occur in 16.3.2.  So should I be submitting this as a bug report?  I don't see a clear way of doing that.

                • Re: Displayport monitor not detected at startup
                  amdmatt

                  Please can you attach a DXDIAG report to your next response? Please don't copy and paste the information into your post.

                   

                  If you disconnect both DVI displays, are you able to get a display from the DP connection on each boot?

                   

                  Have you tried swapping your graphic card positions around to see if that allows the DP connection to work on boot? I'm assuming that the 280x is in PCI-E slot 1?

                    • Re: Displayport monitor not detected at startup
                      christes

                      amdmatt wrote:

                       

                      Please can you attach a DXDIAG report to your next response? Please don't copy and paste the information into your post.

                      Done.

                       

                      amdmatt wrote:

                       

                      If you disconnect both DVI displays, are you able to get a display from the DP connection on each boot?

                      No.  The problem still persists in that case.

                       

                      Also, the 1440p monitor works fine on DVI or HDMI.  Obviously, I can't try a triple monitor setup with that since neither of the other monitors has DP.

                       

                      amdmatt wrote:

                       

                      Have you tried swapping your graphic card positions around to see if that allows the DP connection to work on boot? I'm assuming that the 280x is in PCI-E slot 1?

                      To be more specific:

                      • My primary card is a Sapphire R9 280 Dual-X (not 280X, though it likely doesn't matter here).
                      • My secondary card is an MSI HD 7950 Twin Frozr iii.

                       

                      Unfortunately, the 7950 only has mini-DP, not DP.  Since I don't have an adapter, I can't properly test this.

                       

                      However, I can tell you that the problem persists even after taking the 7950 out.  So it has nothing to do with crossfire.

                       

                      The most frustrating part about all of this is that the monitor is occasionally recognized and I have no idea why.

                        • Re: Displayport monitor not detected at startup
                          amdmatt

                          Next time the monitor does not display an image, please navigate to Windows Device Manager and check the monitor is not showing up as disabled. I had a similar issue with my DP screen recently and i discovered that Windows had disabled it in Device Manager.

                            • Re: Displayport monitor not detected at startup
                              christes

                              So I just turned the computer on to test:

                               

                              On the first boot, all three monitors worked (it seems like it might be more likely from a cold boot, but I can't confirm that)  Three monitors showed up in the device manager.  One of them showed up as being disabled, however.  Enabling and disabling them in the options had no effect.

                               

                              I then restarted the computer and the DP monitor did not work.  At this point, only two monitors showed up in the device manager, and one was still listed as disabled.  Once again, enabling and disabling had no effect.  Upon unplugging and reconnecting, all three showed up.

                               

                              In both cases, I couldn't tell which monitor was which since they're all listed as Generic PnP monitors.

                               

                              Also, here is another symptom that I've discovered.  I'm currently playing through the game Witcher 2.  When the DP monitor is detected on its own, the game runs fine.  However, if I have to unplug and reconnect it, the game refuses to run in full screen mode even after the DP monitor seems to be working fine.  It just gives a a black screen accompanied by the lagged out audio from the intro, followed by the non-lagged audio from the title screen.