Why are DL-3000 (and DL-5900) series restricted to 2560x1440 at 50Hz via HDMI?
 

Hi,

the knowledge base says that DL-3000 and DL-5900 series is restricted to 2560x1440@50Hz via HDMI:

http://support.displaylink.com/knowl...lution-support

The main website says that DL-3000 series are using HDMI 1.3:

http://www.displaylink.com/integrated-chipsets/dl-3000

HDMI 1.3 should be able to do 2560x1600@60Hz according to Wikipedia:

https://en.wikipedia.org/wiki/HDMI#Version_1.3

So why are DL-3000 and DL-5900 series devices restricted to 2560x1440@50Hz?

Hello,

The DisplayLink DL-3000 doesn't achieve that resolution@refresh_rate because the hardware don't allow it.

Are you sure there isn't a confusion between maximum allowed by a standard and minimum required?
Doesn't HDMI standard define a maximum link bandwidth? That's what the page in Wikipedia puts in the table. Then, based on some timings detailed in the table footnote b, the author worked out what a resolution@refresh_rate it could mean as no standard consumer knows what a pixel clock is.

Regards,
Alban

According to your own documentation (see post #1 for example), both the DL-3000 series as well as the DL-5900 series do support resolutions above 2560x1440@50Hz via DisplayPort, such as 2560x1600@60Hz and 3840x2160@30Hz for example.

So, if it can do 2560x1600@60Hz via DisplayPort, then why can't it do it via HDMI 1.3, even though HDMI 1.3 should support it?

PS, by the way: The Wikipedia link in the first post was wrong, here's the proper one: https://en.wikipedia.org/wiki/HDMI#Version_comparison

That is correct. Different interfaces have different requirements.
The same resolution applies to DisplayPort++ as it's really HDMI signals over a DisplayPort plug (in layman's terms).
These parts don't do 5K either, the DisplayLink DL-6950 does.

The Wikipedia page is not the specification used to test or certify any product. The Wikipedia page does not state it is a mandatory requirement, does it? You have missed replying to that question.

If you find contradicting information in the HDMI specification, I will be delighted to go to engineering and ask the question. But I don't see myself using Wikipedia as the source to report a bug... You could clarify the Wikipedia page as it's free to edit or ask for clarification before doing so.

The fact that the chip doesn't do 4K over HDMI can be totally irrelevant to an end product. One illustration could be the Plugable UGA-4KHDMI graphics adapter.


Should you have questions for your design, we can work out the details for what is the most suited to your project.