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