SP4 Dock Dual monitor issue.

[hastyle]

Hey guys,
i just got a second monitor today, tried to hook it up to my SP4 dock but it doesn't wanna connect both monitors. Under display settings its showing monitor 1,2,3 but my old monitor doesnt wanna connect.

So i have a
dell U2713H (old ) DVI to MDP because for some reason DP to MDP stop working.

dell U2715J (new) DP to MDP.

If i disconnect either monitors the other one will work, but when both are connected only the U2713H works.
any suggestions??

thanks

 

[DaveR12]

In my previous job I maintained about 15 Surfaces and a handful of Surface 4 docks. The only way I was able to consistently use multi monitors on the docks was through "Active" adapters like this Cable Matters one.

http://a.co/2YeUXr5

 

[hastyle]

that only supports 1920 resolution!