Changing res to 720 wont work

[joho5]

I have an hd 7870 card and a Samsung 60hz led monitor with native resolution of 1080.

I have tried setting resolution in battlefield 4 down to 720 60hz and 720 59hz...all it does is blink and wont show a picture.

I want to be able to do this sometimes to test functionality on a lower resolution...whats the cause of this?

 

[ahmeday2012]

Try to reduce the windows resolution and then try to open the game like that