Monitor Keeps Flashing On and Off

[kendallkoh]

Hi,

Recently i bought another Dell U2515H, and now my current rig as seen on the right side is rocking double U2515H. But i keep getting problems where my left monitor (older one) keeps flashing on and off.

Details are as follows:

Left Monitor
Older of the two by 1-2months
miniDisplayPort Cable that came with the monitor

Right Monitor
Newer of the two
HDMI Cable

The flashing doesnt occur all the time, but at random times. I have no idea why. Could it be that my GPU cant handle 2 of these 1440p monitors? Cant be right?

 

[enenyi]

Try with both on HDMI. Could be Displayport handshake connection working up.

 

[kendallkoh]

I cldnt find another hdmi cable.
But i've got 2 displayport to displayport cables running on both monitors.
The flashing on and off still happens.
Any idea why?

Edit: A restart of my computer seems to resolve it. But i wldnt want to restart my computer everytime this happens.