Re: [gentoo-user] black screen on boot when udevevents are processed

[lee]

<wabenbau@×××××.com> writes:

> lee <lee@××××××××.de> wrote:
>
>> <wabenbau@×××××.com> writes:
>>
>> > lee <lee@××××××××.de> wrote:
>> >
>> >> Hi,
>> >>
>> >> I'm getting a black screen during booting, with the last message I
>> >> can see being that udevevents are being processed.
>> >>
>> >> This happens with an NVIDIA GTX770 connected to a 4k display via a
>> >> display port cable, and only when the monitor is configured to use
>> >> display port 1.2 rather than 1.1.  With 1.1, I can get only 30Hz
>> >> refresh rate, so I want to use 1.2, which should allow 60.
>> >>
>> >> Installed are nvidia-drivers 343.36.
>> >>
>> >> Do I need a very special display port cable for this, or what might
>> >> the issue?  Both the graphics card and the monitor should be able
>> >> to do the full resolution at 60Hz just fine.
>> >
>> > You need a DP cable that is able to handle a resolution of 4k@60Hz.
>> > Not all DP cables can do this.
>>
>> Hm, I bought this cable today, so I'd think it should be ok --- but I
>> didn't explicitly specify that it must be one that does 4k@60.  I
>> didn't know I might have to.
>>
>> Is there any way to tell?  The sticker on the package only says DP/DP
>> 2.0m.
>
> It should be certified to DP 1.1a at least.
>
> Excerpt from
>
> https://web.archive.org/web/20140327103747/http://www.displayport.org/faq/
>
> ----
>
> Q: Where can I buy a DP 1.2 cable? Most of the cables are certified to DP 1.1a.
>
> A: The DisplayPort version 1.2 standard was designed to utilize the
> Standard Display cable. We did this intentionally to avoid customer
> confusion. A DisplayPort cable is a DisplayPort cable; EXCEPT if it a
> “reduced bit rate” (or RBR) cable, which is typically a 15m cable
> designed for projector applications, and they only support up to
> 1080P; OR if it is an active cable, which will not support the new
> HBR2 rate introduced in the DP 1.2 standard.
>
> So a cable that was tested to meet the DP 1.1a requirments also meets the DP 1.2 requirements.
>
> ----
>
> But this is theory. I've made the experience that some cables doesn't
> work with 4k@60Hz although they are so-called 1.1a/1.2 certified. I've
> bought four faulty cables before I found the two that I'm using now.
> One of the faulty cables doesn't work at all at full resolution, the
> others are working but the picture had a lot of errors and was sometimes
> black for some seconds.
>
> The two cables which I'm using now are a CROMO 41532 (2m length) and a
> CROMO 41533 (3m length).
>
> Do you have the opportunity to test the cable with some other system,
> e.g. some live system (knoppix?) or some windows system? I would do this
> first before buying a new cable.

Thank you very much for all the info!

I finally got a cable that works.  It's from Delock and says 82771 on
the back of the package where the EAN code is.  I like it, it seems to
be good quality, and most importantly, it works.

However, I can see the BIOS and the boot manager menu, then during
booting, the screen goes black and the monitor says "no signal"
(probably when the nvidia module is loaded).  So I logged in blindly and
started X11 and got a picture again.

The monitor info says 4k@60Hz in the BIOS and when X11 is running.  So
there must be some setting which causes the graphics card to blank out
on the console.

Any idea what that could be?


-- 
Again we must be afraid of speaking of daemons for fear that daemons
might swallow us.  Finally, this fear has become reasonable.