Hi ReventonAvantador,

Thank you for writing to the Dell Community Forum.

Please try the below steps,

• Reseat the power cables to the monitor firmly.

• If you’re using the a surge protector, try connecting it to the wall outlet directly.

• Swap the power cables with your system and check if the issues remains.

Please reply if you have any further questions.

Thank you for the reply,

I have tried the way, my 1st monitor connected directly to graphic cards is better now. No 'flickr' up to now. will continue to monitor it. 2nd monitor occationally still would flickr but not as often. 

1st monitor have some minor flickr once awhile after 2nd monitor daisy chain from it.

Mind elaborate why would this happen ?

I'm using PowerColour R9 380x GFX

You should remove the dual monitor setup and test each monitor by itself on the computer and see if the issue happens on both, or just one.

Tried individual testing on each monitor. everything is good, But when connecting to dual monitor. It would start flickr occationally.

That would point to the computer video card ports or the cabling as the culprit, not the monitors. Or that the video card driver is not fully supporting the MST DP 1.2 daisy chain.

Computer video DP out --> U2417H DP to mDP cable --> #1 U2417H mDP in (MST On)
#1 U2417H DP out --> U2417H DP to mDP cable --> #2 U2417H mDP in (MST Off)

or

Computer video mDP out --> U2417H mDP to DP cable --> #1 U2417H DP in (MST On)
#1 U2417H DP out --> U2417H DP to mDP cable --> #2 U2417H mDP in (MST Off)

I'm using Powercolour R9 380x edition. Read that it has a full size display port 1.2 and can support up to 6 monitor when dp port.

Computer video DP out --> U2417H DP to mDP cable --> #1 U2417H mDP in (MST On)

#1 U2417H DP out --> U2417H DP to mDP cable --> #2 U2417H mDP in (MST Off)

Graphic Card DP to 1st monitor MDP (MST ON), 1st monitor DP OUT  to 2nd monitor MDP (MST OFF)

I suppose that is what you mean, i do not have mdp port in my graphic card so i'll skip the 2nd step.

Tried it but still flickr, contacted Powercolour on the issue they recommend the mention below

please try to solve this status by change refreas rate to lower setting

(i.e. 30Hz ) , or , please also check the quality of DP cable and reduce

DP cable from display card to MST hub .

Testing a 3rd party cable is an option. You did install the latest R9 380x driver directly from AMD?

I'm currently testing 3rd party cable. monitoring it

Yes i have latest install the latest driver for my graphic card

Problem still occur, even using Dp to Dp for both connecting to graphic card - monitor - monitor.

Request you to test these monitors, on a different system. Also request you to test in safe-mode, if it is working fine. Then uninstall the video driver completely from the system and install the latest one.

Please reply if you have any further questions.

Tested in safe mode, both monitor are working well.

Reinstalling to latest video driver. Reboot to normal mode, problem still persist but not often.

Tried diagnostic my video card. It seems there is a drop in voltage when connected to 2 monitor.

Thanks for trying all the steps, as it is working fine in safe mode. Looks like a driver issue, causing the problem. Please reinstall the OS on the system and then install the latest video driver.