4k Monitor Gets Blurry When 2nd Monitor Is Plugged In

[KeltronX]

I just recently got a new 4k monitor to use in an extended, dual-display setup. For some reason though, it works fine until I plug my 1080p display in as well. The second I plug in the 1080p monitor, the 4k monitor goes fuzzy and says that the max resolution is 1440p. Then, I unplug the 1080p monitor, and the 4k monitor goes back to being its native 3840X2160.

I don't know what the deal here is. If anyone can help, I'd really appreciate it. I've spent all day trying to figure this out, and I can't find any solution.

If it matters, My 1080p display is plugged into a gtx 980 via HDMI, and the 4K is plugged into the same card via DisplayPort. Both are 60hz monitors.

UPDATE: I have tried setting a custom resoltion of 3840X2160 to override the automatic 1440p. This only makes it say that it is running in 4k, but it's pretty obviously still 1440p at most.

 

[iamacow]

Hmm that strange. Will its obvious the blurring comes from the 1440P resolution. I don't see why the 4k monitor would be affected with a second monitor in HDMI while the main one is using DisplayPort.

Maybe some HDCP settings is forcing the 4k monitor to run at 1440P when HDMI is used.

 

[KeltronX]

Okay. So, I didn't find out exactly why it did what it did, but I found a work-around. I just switched the cables the monitors were using, and the 4k is displaying a 3840x2160 image just fine.