[mythtv-users] Issues with HDMI after TV Turned off

Peter Buelow goballstate at gmail.com
Sun Nov 15 20:54:50 UTC 2009

>> You did not mention what video card/chipset you are using, but nvidia has worked well for me. I know that the nvidia cards look for analog devices first, digital next. If neither is found then the video just gets sent out the analog (VGA) port. Even with my TV off, but still connected to power the video card detects that it is connected and will use the digital output.
>> On both of my HDMI connected TV sets I can see the entire boot process over HDMI. Both sets are connected to GeForce 9500 cards. One with native HDMI and one with DVI->HDMI. One thing you may want to do is see what video modes the TV reports. Try running X with the log set to verbose 6. Then check the log for what resolutions the TV set is reporting.
>> My TV sets will display 480i over HDMI which is about what the bios and initial boot screens run at. Once X starts
>> the nvidia driver takes over and gives you much finer control. I have not seen any problem with turning the TV off. Do you remove power or just use the on/off built into the TV?
>> You could try leaving the TV turned off, but connected to power. Boot into X with verbose 6 for the X log. Check the log and see if your video card can detect the presence of the TV. My cards do even with the TV off. If your card does not that may be the cause of your problem.
>> Cheers,
>> James
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> I did mention in my first post that its an NVIDIA 8400gs.  It works well in vdpau.  I did run x with verbose 6 as you suggested and I see the whole range of potential video modes from 1080i down.  They are all visable and valid.
> Perhaps there is something in my bios that I should look at to ensure it selects the correct video card or port on boot?  Not sure - that may be why  Idon't see the video on boot.
> As for the screen not coming back, I'm not sure what could be happening.  X seems to see the tv even when its off so perhaps its the TV or something.  Has anyone heard about a possible bios update for the TV?  It's a Daytek LM37 and has a supposed serial port for bios updates but I've yet to find one.
> Norm
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Interesting. I've been hunting for a solution to the same issue seemingly. The TV off problem, I can actually watch the system boot which is odd, I couldn't do that until just recently.. And actually, it happens to me even if I change inputs. After it sits for a few minutes on a different input, and then I switch back to myth, the display is blank (however, TV is not in DPMS, just blank). I'm using an Nvidia 8300 GT MB and my TV is an LCD, LG 47LH40, running F11 with all updates from atrpms. Makes myth effectively useless right now (although this isn't myth's fault that I can figure). Hoping someone knows.

Things I've tried. Manually setting a modeline and disabling EDID in the xorg.conf, no change. Completely disabling DPMS using all the options possible in xorg.conf, no change. I think it's the TV actually, but it's hard to say. My DVD player and TV don't have this issue, and both of those use HDMI as well.


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