What you really need is a slightly newer video card (with displayport out) to take advantage of the displayport(s) on the monitor.
I think you're doing everything right, as that's how my HDMI monitor is adjusted.
Seeing as you're using an old vid card maybe you'd be better off with an older catalyst suite like 12.10 which is problem free here.
#1: FX-6350, Antec Kuhler 920, MSI 970 Gaming, Asus 5870/V2, ASUS Xonar D2X, GSkill (F3-14900cl9d-8gbxl), Antec Truepower New 750, Arc Midi, Win8.1pro x64
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