How to set HDMI resolution?

Discussion in 'AMD Flavor' started by Luke M, Apr 5, 2018.

  1. Luke M

    Luke M Limp Gawd

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    System: A8-7410 (integrated graphics) / Win10

    The AMD graphics are always outputting the display's maximum reported resolution (which happens not to be the native
    resolution...it's a projector, not a PC monitor) regardless of the system resolution setting. The software resolution is correct, but the HDMI port is still outputting the wrong resolution.

    How do I set the native HDMI resolution?
     
  2. Maddness

    Maddness Gawd

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    What resolution are you trying to set it at. Also have you tried a different HDMI cable.
     
  3. Luke M

    Luke M Limp Gawd

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    1280x800 (60hz)

    It's not a hardware problem. It's strictly software.

    The GPU scaling option is of course off, but the driver seems to ignore it. Most of the time. Seemingly at random, it does output without scaling like it should. But I can't get it to work reliably.

    Unless I find a solution, my options are either to spend $80 on an EDID box, or else junk the AMD and get an intel system.
     
    Last edited: Apr 7, 2018
  4. Brian_B

    Brian_B [H]ard|Gawd

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    Does the resolution change as expected when using any other video display (dunno if it's a laptop with it's own screen or not)? Have you tried the HDMI on another HDMI device?
     
  5. Luke M

    Luke M Limp Gawd

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    The display I'm using for testing purposes (after discovering the problem) is a normal 1920x1200 PC monitor (not laptop). I can verify the resolution in the monitor menu. It should be 1280x800 (and sometimes is), but usually it's 1920x1200, i.e. GPU scaled up from 1280x800.
     
    Last edited: Apr 7, 2018
  6. Mega6

    Mega6 Gawd

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    maybe this will help.
     
  7. Luke M

    Luke M Limp Gawd

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    I can set the Windows resolution, that's not the issue. The problem is setting the hardware output resolution. They aren't the same because AMD scales up the Windows resolution to the maximum reported resolution of the display (even if the aspect ratio is wrong...and GPU scaling is off (does that option even do anything?))

    Anyway, I found a workaround which seems to work, mostly. That is to override the EDID in the registry. It still has some problems including sometimes bugchecking the AMD driver...
     
  8. Luke M

    Luke M Limp Gawd

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    It occures to me that maybe the problem is that the AMD driver falsely believes that the HDMI output is actually an internal laptop display, for which forcing GPU scaling to be always on would make sense. Just a guess.
     
    Last edited: Apr 8, 2018
  9. BigBadBiologist

    BigBadBiologist 2[H]4U

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    Is the projector the only display plugged in? I've had similar issues with a projector/monitor combo. Individually, they work fine, but windows decides to make some assumptions when they are both plugged in.
     
  10. Luke M

    Luke M Limp Gawd

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