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

[Fernando Rodriguez]

On Wednesday, September 02, 2015 12:29:36 AM lee 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.
>
> > But if you use the cable that is delivered with your monitor, it
> > should work for all resolutions/refresh rates as long as it is not
> > broken.
>
> Unfortunately, the cable that came with it has a normal size connector
> on one end and a small size connector on the other.  Both the monitor
> and the graphics card require the normal size connector, so I cannot use
> that cable.  That's why I bought one ...
>
> > Sorry, but I can't say anything about the rest of your questions.
>
> Np; when I don't have the right cable, it'll never work anyway.  Now I
> know what I need to look into first :)

According to [1] a DP cable is a DP cable, so it should work. The exception is 
if the cable is marked as RBR (Reduced Bit Rate). But depending on the brand 
and where you get it's not unlikely that it's RBR but not marked as such. They 
got a list of certified cables on the last paragraph.

1.http://www.displayport.org/cables/how-to-choose-a-displayport-cable-and-not-get-a-bad-one/
-- 
Fernando Rodriguez