U2711, HDMI, 2560x1440?

HDMI is a video mode and not a graphics mode i.e native resolution. The highest HDMI can go is 1080p which is 1920x1080.

Though the OLD HDMI 1.0 did only support 1080. HDMI 1.3 supports Deep Color and 2560×1600. So why does U2711 not accept it via the HDMI input?  

The U2711 is able to do the following:

12bit internal processing which tested HDMI 1.3 with deep color

I would look to the video card driver or the video card itself as the culprit. Understand, the monitors HDMI is passive. It only does what the video card and video card driver direct it to do.

Chris,

So you are saying that the U2711 can accept 2560x1440 via a HDMI 1.3 connection?

Regards

The revision of HDMI doesn't matter. It should do 2560x1440 for DVI, HDMI, and DP (DisplayPort) IF the video card and video card drivers are capable of transmitting that signal.

Chris,

I contacted Dell technical support before I bought this monitor because although most (but not all) sales people thought that the full native 2560 x 1440 resolution could be displayed over HDMI they were not 100% sure.  Dell technical support reassured me that there would be no problem at all – no caveats or anything!

07/07/2010 – “HDMI is a video mode and not a graphics mode”.

07/07/2010 – “The highest HDMI can go is . . . 1920 x 1080”.

17/06/2011 – “The monitor’s HDMI is passive”.

17/06/2011 – “The revision of HDMI does not matter”.

17/06/2011 – “It should do 2560 x 1440 for . . . HDMI”.

i) HDMI maybe a ‘video mode’ but it is equally capable of transmitting and thus displaying graphics.  Basically, it is just a method of connection.  I appreciate that HDMI is often used for TV / Movies and currently the highest broadcast is 1080p; however, that does not make 1920 x 1080 the maximum possible resolution over HDMI.  Higher resolutions can be and are being captured and will inevitably become more popular in the future.  Furthermore, it appears that the maximum over HDMI is a bandwidth / MHz restriction which is a product of the resolution, refresh rate and color bit depth.  As such, the higher resolutions could potentially be supported by reducing the refresh rate and / or color bit depth to keep within the maximum bandwidth / MHz; as has happened with HDMI 1.4 which supports 4096 x 2160 at 24 Hz for 8, 10 and 12 bits per color channel.

ii) I have encountered multiple people at Dell telling me that the U2711 both can and cannot support the full native 2560 x 1440 resolution over HDMI.  Perhaps everyone can get their story straight once and for all.

iii) Can you 100% guarantee that the monitor’s HDMI port is passive?  Many appear to think that the monitor restricts the input to 1920 x 1080.  Similarly, the monitor’s documentation states “Set the screen resolution to 2560 x 1440 (DVI and DisplayPort) or 2048 x 1152 (VGA) or 1080p (HDMI, Component)”.

iv) As SkyguyAFFI pointed out above, the revision of HDMI does matter.  HDMI 1.0 could not support the monitor’s full resolution or color depth, let alone both.  HDMI 1.3 and above can support up to 340 MHz (10.2 Gbit/s) and the U2711 only requires 241.5 MHz for 2560 x 1440 at 60 Hz & 10 bits per color channel.  However, all the links in the chain must support the desired resolution and color depth (i.e. video card, driver, output, cable, input and monitor).  For example, the cable must be High Speed (Category 2) as Standard (Category 1) cables certified under HDMI 1.3 have only been tested to 74.5 MHz and thus only support 720p and 1080i.  Furthermore, Deep Color support is an optional extra that may or may not be implemented in a specific product.

I am a little confused regarding the advertised “12-bit internal processing” that “enables 1.07 billion colors”.  Surely only 10 bits per color channel are required for 1.07 billion colors (i.e. 2 ^ (10 bits x 3 color channels) = 1.07 billion colors).  Are the color numbers (i.e. 8 or 10 bits per channel, depending upon the output) color managed via 12-bit internal processing to produce more accurate colors?  If so, could the problem be with the system being fooled into thinking 12 bits per color channel are being used and thus limiting the resolution to 1920 x 1080 at 60Hz, which may be the maximum possible for a 36 bit color depth on HDMI 1.3?

In summary, can you absolutely, 100%, confirm that the full native 2560 x 1440 resolution at 60 Hz and 30 & / or 24 bit color (i.e. 10 & / or 8 bits per color channel) is possible on the Dell U2711 over an HDMI to HDMI connection?  Theoretically it is definitely possible; however, have you actually seen it working correctly?

Guys,

I have the U2711 Monitor and I want to buya 3350 vostro.. Will I be able to use this on 2560x1440 with the laptop hdmi?

Thanks!

The U2711 manual here states the maximum resolution via HDMI is 1080p. Max via DP is 2560x1440. Guerdon, have you tried forcing 2560x1440 via HDMI yourself? Did you just save the EDID via DP, and then force the video driver to use this EDID on HDMI? I'm considering doing that, since I have a laptop which appears to be able to put audio out via HDMI, but not via DP.

btw, read what was posted by: jd1977   03-23-2011 at 03:00:05 PM

Read this.

www.tomshardware.co.uk/.../293955-13-displayport-cable-providing-power

Its applies to HDMI as well, Not sure what spec my lead is but I tried 3of them. Instead I had to connect my laptop to a HDMI - DVI adapter to run max res using a problem HDMI lead. It's working perfectly (at the moment) I will have to see if there are any changes tomorrow as they were on HDMI, day 2, today. My sky box runs through HDMI at 1080i with no issued.

I'm running an XPS M1530 with a nVidia 8600 GTM.

I've had so many issues including 2 hours of research yesterday just to get max res to work through creating a custom resolution.

If there are any further issues it's going back, I'm not waiting 1 year for it to act up like some people came across in the thread.

The article to which you refer is regarding power provided over the cable, which I assume you are stating is an issue over HDMI in the same way as it is over DisplayPort.  This is a related but different question.

The O.P. is purely about being able to obtain full (i.e. 2560 x 1440) resolution over an HDMI connection to a U2711.

As mentioned above, this is possible via a custom resolution or by manually editing the EDID file (or preferably if Dell would create and issue something to update the EDID file to include 2560 x 1440 as a selectable option).

To be honest, I'm a bit confused about your post.  You mention using a HDMI to DVI cable to run max resolution and then mention a sky box running 1080i.

Firstly, I'd be very surprised to learn that you have a HDMI to Dual Link DVI cable (even if the cable looks like it has a Dual Link DVI connection) as apparently you need active electronics to convert the single link HDMI signal to a Dual Link DVI signal.  Otherwise, its is acting as a HDMI to Single Link DVI cable which I understand would not have sufficient bandwidth to carry the full 2560 x 1440 resolution.  However, if you're referring to 1920 x 1080 as being the full resolution due to Dell's stated native resolution over HDMI then this would make more sense.

AFAIK, in terms of bandwidth requirement, 1080i is half of 1080p (i.e. Dell's stated native resolution of the U2711) which is in turn half of 1440p (i.e. 2560 x 1440 progressive scan).

As for jd1977's comments on the article, s/he appears to simply be asking for a HDMI to DisplayPort cable recommendation, so I don't understand the relevance (and s/he's connecting to a U2311h not a U2711).

Regardless, I suggest you create a separate thread for your problem; however, I concur that there appears to be unresolved issues with power saving / shut down / display driver crash & reboot etc with DisplayPort and HDMI connections to the U2711.