Hello Hadog,

Sorry to hear that.
Which MST Hub do you have (for instance … CSV-5300A / CSV-6400 / CSV-6200H)
We have heard more initial issues with some Driver versions for RX generation with regards to use of Eyefinity feature.
Which driver version are you currently using ?

hello and thanks I am going nuts here hahahah I have the 5300A uding the lastest drivers 18.2.1 been trying every cable/adapter I have tried a different monitor…..clean uninstall of drivers fresh install…….I have two AMD cards (not in the machne at the same time) and they are both having the same problem

would it be possible that the monitors are the problem….using Acer monitors hdmi connection….they are not new 4 years old at least I have been trying every combination…the best I can do is to get the three up and running but when I try eyefinity I get the input not supported doesnt matter if I use your hub or individual active adapters

Hello Hadog,

An MST Hub is an active device so you should use passive adaters plus normal HDMI cable that comes with the screens, to connect your HDMI Monitors.
Like these: CAC-1001
http://www.club-3d.com/en/detail/2373/displayport_to_hdmi_passive_adapter/

Any particular reason you choose for the CSV-5300A instead of the CSV-5300H ?

Hello Hadog,

IF your MST Hub ahs HDMI outputs than you have the CSV-5300H.
And no then you would not need adapters, just normal passive HDMI Cables to go to Screens.

when the 5300a arrives do I use passive or active adapters? Just want to make sure

passive adapters

please do 🙂

nope same issue…input not supported …running the new hub 5300a with three passive adapters…….one monitor works…when i hook up the second it duplicates the first monitor screen (I can not extend the screens no option appears  to do so  When I hook up the third monitor I get input not supported on all three….running the r9 200 series card will try the other card tomorrow not happy at all

Hello hadog,

That indeed does not sound good, which is very odd.
To make Eyefinity work, you need WIN Vista or newer and use the DP1.2 ouput on the Graphics Card. MultiStreamTransport (MST) feature is supported by DisplayPort 1.2 spec and WIN, meaning grpahcis cards with DP1.2 ouput are able to output multiple video streams over a single DP1.2 output. An MST Hub is able to recognize and distribute those video stream (with sound even) to connected screens.
Some screens need to be set to DP1.2 for the DP input in the menue of the screen (factory default would be DP 1.1).
MST Hubs are active devices and do not work well together with other active devices like Active adapters / Cables/ Switches / CrossFire / SLI setups.
Thats it, shoul dbe like “nothing more to it” …

could also be a driver issue … perhaps try a driver version from before RX400 / 500 series came out. 
Not sure if your card will accept it but 16.8.3 was a really good driver and 17.2.1 was also quite ok.
https://support.amd.com/en-us/download/desktop/previous?os=Windows%2010%20-%2064

As you know I have been going through this problem for a while and I have tried almost everything I can think of and what you suggest…so I go back to the beginning,,,input not supported ….the monitor is the input, But they appear fine settings are all in order I have a new fourth monitor hanging around so I hook that one up thus removing one of the Acers……everything works …..hub is fine eyefinity is fine everything is fine (unless it all comes crashing down tomorrow hahahahah)  Many thanks for your support  much better than AMD and MSI who still havent replied!!!

glad to hear you got it working 🙂
Thanks for the feedback.