@itsyoung!!
@Liquid 's post made me think of something.
The last few days aside, I think you really should go with 3 of those 1080p monitors. You said you just care about online play. Having 3 monitors increases your fov so much that you'll be able to see opponents you never saw before. Some even think it's so unfair that they call it cheating. It should immensely help you out competitively. Much more so than 1440p or a nice 7.1 headset. You have 3x the viewing area now. Your peripheral vision can be used to spot opponents that you'd have to turn to see before. I'm not into competitive gaming like you, but shyt is like cheating on a first person shooter. Here's just one of the many articles talking about it.
http://www.digitalstormonline.com/unlocked/pc-gaming-101-multiple-monitors-idnum27/
No need to talk about the GPU requirements for this, you can look it up yourself or play on medium or something, since you don't really care about graphics.
Something to consider, if you're really into online, competitive gaming like that