New monitor picture grainy. Old monitor smooth. Both BenQ.

[Dubsko]

Hello all!

So I just bought myself a new computer and put it together, and while everything went pretty smooth, there's one thing that's is everything but smooth: my monitor's picture.

My new "BenQ 24' LED Gaming Monitor RL2455GM" picture is just very... grainy and jagged around the edges, which is dissapointing to say the least considering I figured I'd have quite the visual upgrade with new GFX card, HDMI cable and monitor.
Even my old monitor on my old computer (BenQ e2200HD LCD) connected with DVI has a way smoother image.
I tried connecting my new computer to my old monitor with the same HDMI cable and it worked out perfectly, nice and smooth picture.

So my question is: What gives? Is there something I could have done wrong? Some setting I need to fix? Or is my new monitor "broken" or just plain bad?

EDIT: The lighting seems... off aswell. Poor quality and too bright?

Thank you in advance for any help or insight into the matter! I'll leave my specs underneath. If there is any other information that would be useful, please let me know!

Windows 7 Ultimate 64bit
Gainward GeForce 770GTX 4gb
ASUS Z87-PRO Socket-1150
Intel Core i7 - 4770K
Corsair Dominator RAM 16gb 1866mhz
Corsair SSD 240gb Force Series GS
XFX ProSeries 850w PSU

The monitors, as I mentioned, are:
NEW: BenQ LED Gaming Monitor rl2455hm
OLD: BenQ LCD e2200HD

 

[Dubsko]

Seems it was one of the preset "RTS" modes for the monitor that was off. Changed it to standard and tweaked some of the other settings and it seems to be working fine now. Thanks anyway!