Corprive :
I would like the biggest screen without an excessive price, from my research this point is 22" (I could be wrong).
This GPU can handle one monitor in 2560x1600p, is it able to handle two 1920 x 1080? If so, this will be a nice resolution.
Price: ~100-125$ for each
EDIT: A 27" 2560x1440 costs ~800$ and my budget for the monitors is 250$
Yes, a high-res monitor is OUT (though a good one is about $480 not $800 just FYI):
http://pcpartpicker.com/part/asus-monitor-pb278q
*I'm still confused on how you intend to use them because as I said GAMING on two screens isn't a very good experience due to the GAP.
Yes, you can support at least three (possibly four) monitors at 1920x1080 so that's not an issue. Your GAMING performance is based on the effective RESOLUTION chosen for the game. For example, if it was a single monitor that would usually be 1920x1080 in your case (about 2 Million) though you can chose a lower resolution that scales (like 1600x900).
I mention the scaling because you might have to do that if gaming over two monitors since that DOUBLES the number of pixels if using as a "single" gaming screen (which roughly HALVES the frame rate).
SCREEN SIZE has nothing to do with performance though I usually don't recommend above 24" for 1920x1080. How CLOSE the screen is does affect seeing the gap between the individual pixels so if you push the monitor to the rear then 24" is probably fine.
*EXAMPLE MONITOR (some with rebates; speakers likely suck but weren't a factor):
$140 (24", 1920x1080, 2ms response):
http://pcpartpicker.com/part/asus-monitor-ve247h
$90 (21.5", 1920x1080, 5ms response):
http://pcpartpicker.com/part/hannspree-monitor-he225dpb
SUMMARY:
I hope this helps, but don't just look here look at Amazon etc to find out as much info about each monitor (light bleed issues etc. all monitors statistically have issues).
In very BASIC specs I recommend:
- 1920x1080
- 5ms or LESS response time
- generally good customer comments
- look up the WARRANTY (3-year if possible; *I've had bad dealings with ACER quality in the past with many people. I can't speak to overall support now)