[mythtv-users] No Display
anothersname at googlemail.com
Mon Feb 7 07:39:44 UTC 2011
Sorry I've come to this a bit late so if this has been covered please excuse me.
Do you have another machine (GOODPC) which you can logon to the
machine with the problem (BADPC)?
If you do I suggest the following.....
Install x11vnc onto BADPC.
ensure you open port 5900 on your firewal on BADPCl
copy the script I've sent to you offlist onto BADPC, this script is
for a Fedora box so you may need to modify if subject to your distro.
from GOODPC logon to BADPC via ssh using the root account, i.e. ssh
root at BADPCipaddress
when logged on to BADPC run the script i've sent you, you should see
go through ending in "....x11vnc waiting on port 5900...."
on GOODPC run the vnc client (for Fedora it's tigervnc) thus tigervnc
You should now be logged onto your live desktop on BADPC
open a terminal session on the BADPC desktop
using xrandr find out what modes are supported and what mode it's
running in, read the xrandr manual to see what you are allowed to
hopefully you should be able to play with xrandr to get a mode that
outputs to your screen correctly.
On 06/02/2011, R. G. Newbury <newbury at mandamus.org> wrote:
> On 02/06/2011 10:39 AM, Jay Ashworth wrote:
>> ----- Original Message -----
>>> From: "Andre"<mythtv-list at dinkum.org.uk>
>>> Sounds like the TV is the issue then, it's a long shot but if you are
>>> running nvidia v260 drivers it might be worth trying the two different
>>> output modes now available. RGB is the default but YCrCb is now
>>> selectable in nvidia-settings. I've seen various TVs behave quite
>>> differently when given YCrCb instead of RGB (sometimes called TV mode
>>> rather than PC mode, although there's a little more to it than just
>> To me, off hand, this sounds like:
>> The TV expects that the bitstream on the HDMI cable will always include a
>> video *and* an audio stream, *even if there's no audio in that stream*,
>> the video card on the PC *isn't generating an audio stream*, unless
>> actual, y'know, audio to put there. Therefore, the TV intemperately
>> to display the perfectly good video.
>> Finding a way, probably in the Xorg screen config, to force that card to
>> send an audio stream all the time, will I think be the solution...
>> if it's possible. The people who work on the drivers for the card you
>> are probably the best people to be asking: this is probably going to be a
>> general problem.
> I think your card and hardware are fine.
> Your earlier recounting of the problem was not quite clear to me, but it
> sounded like you can get a desktop, but that it 'goes away' when
> mythfrontend starts. If that is correct then the first step is to stop
> any autostarting of myth.
> And CONFIRM that this is a myth problem and not an existing OS problem.
> I have a 3 year old 37" LG flatscreen. The HDMI inputs are *not* all
> the same. One of them is slightly different than the others and is the
> one the TV expects will be used for PC input. ( I pipe the audio output
> of myth directly to an amplifier and then to audio speakers and never
> have any sound from the TV when using myth...so I think this may be a
> misleading item.)
> You might have to try each input in turn. THankfully the remote has that
> dedicated button in the top right corner! (Or the buttons on the side of
> the TV).
> It seriously sounds like myth is forcing a resolution which the TV does
> not like or the video chipset will not accept and output.( But the
> desktop resolution is fine, if I read correctly)
> If you can get a desktop screen and log in (without autostarting myth)
> then the hardware is all right as is the resolution settings *for the
> In which case, you need to get into Setup -> Appearance and set *myth's*
> resolution to something like 1024x768. If you cannot get into there
> without losing the signal, then you will have to poke the Settings table
> At a mysql console, try
> mysql> select * from settings where value like "%Vid%";
> select * from settings where value like "%Resolution%";
> This should give you a largish number of rows. You are interested in the
> GuiResolution, GuiHeight/Width, VidModeHeight/Width and
> TVVidModeResolution entries which have screen size values. You need/want
> them to be 1920x1200 although you might want to test using 1024x768.
> In your particular case, the GuiVidMode, GuiHeight,GuiWidth entries are
> likely the culprit if this diagnosis is anywhere near correct. You will
> need to:
> mysql> update settings set data = "1360x768" where value = "GuiResolution";
> My LG TV would NOT accept 1368 or 780 as proper sizes. I need 1368 for
> width, and 768 for height. So you might need to use 1912 and 1192. (The
> 30" Dell monitor at work is quite happy with 1920x1200 though!).
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