He is correct in that with a GTX 690 you have the horsepower to run any monitor that you choose to buy. The new monitors coming out now are featuring the 2560x1440 resolution and I don't know if they have that resolution in a monitor less than 27".
I have two GTX 680's and I went with a 30" monitor running 2560x1600 and I won't be going back to 1920x1080 , gaming is flat out amazing on this monitor and is massivly enjoyable.
What you can consider is a 1920x1080 monitor that is 24" and has a 120hz refresh rate.http://www.newegg.com/Product/Product.aspx?Item=N82E16824014288http://www.newegg.com/Product/Product.aspx?Item=N82E16824236206
If you want to go with a monitor that has the 2560x1440 then you can look at this Samsung.http://www.newegg.com/Product/Product.aspx?Item=N82E16824001523