[branpute]

[quote author="Official HeadlessGhost Hardware Developer Response"]
Good morning Nicole – thanks for your email.  Looks like a tricky problem you have here.  In the first instance – the headless ghost only has limited support display port as discussed here: https://www.kickstarter.com/projects/devjoshi/headless-ghost/posts/1035927 And while you aren’t directly using display port, there is a chance that it causing some issues.  According to the Spec sheet the EDID versions supported by the hub are compatible with the headless ghost which means that the display modes should be being picked up properly.  As you surmised in your post – even though you select a lower resolution the hardware is operating as if there is a 4k @240hz display attached. For now I can’t say why.  If you like I can provide the EDID file and the club3d guys can take a look at it. I fear that this won’t solve your issue in the short term however.  Alternatively, I could provide you with a different EDID file which doesn’t go all the way up to 4K. Let me know what he specs are that you need and I’ll tweak it for your needs and then you can flash it onto the module using power strip. If you aren’t comfortable doing that I’d be happy to do it for you if you shipped it back to me.  I’ll take another look into what might be preventing you from selecting the resolution you need with the current firmware but without a media hub to test with I may not figure it out.  Let me know what you’d like to do next,Warmest regards from London,Dev
—
Headlessghost.com@headless_ghost
[/quote]

So what we are going to do, is attempt to flash new EDIDs provided by Dev Joshi in London, and that should theoretically fix the bandwidth issues since the MST Hub will no longer be eating up 4k@240Hz bandwidth (even though I am actually telling the adapter to run at 1920×1080@75Hz, (and for all intents, it works as it should, but keeps eating up DP bandwidth of 4k anyway).

I hope flashing the EDID too many times doesn’t damage the HeadlessGhost adapters, but if this fixes the issue, I will be very happy.  I am also asking Dev Joshi if he can share how he generates the EDID files themselves, that way I can dynamically test different resolutions and refresh rates on the MST Hub. 

[branpute]

I have contacted the manufacturer directly, and i’m currently awaiting a response.  I hope for a quick answer and hopefully a solution! 🙂

[branpute]

[quote author="RoyalKing"]Hi Branpute, the following link leads to AMD’s EDID utility which lets you read and save the EDID info. Can you read and send us the info? Then we will check with AMD if there is a solution available to this issue. Thanks! 

http://developer.amd.com/tools-and-sdks/graphics-development/amd-edid-utility/[/quote]

 

I have enclosed the EDID binaries and tiled textfile information for one of the S242HL LCD 24″ Monitors, as well as one of the HeadlessGhosts.

You can find the aforementioned files here:

Download Here

[branpute]

[branpute]

Unfortunately, I cannot say for certain if the displayport 3-way splitter would be capable of splitting a signal within another HDMI splitter down-the-line like that given chart depicted, especially if you run into displayport MST Hub lane bandwidth issues pushing that many displays.

On the bright side, I did take some creative liberty and used Google’s Draw.IO platform to make you a nicer looking diagram. 🙂
[img]http://insights.club-3d.com/wp-content/uploads/2015/05/Club3D-Diagram-1.png[/img]

[branpute]

Additional Information: I am running 2x AMD R9 290X graphics cards in a CrossfireX configuration.

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