Well, I'm gonna tell you how I did it, because my screens have the same connectors as yours.
One to HDMI, one to DVI, and one using an ACTIVE adapter (from XFX) miniDP-DVI to DVI's third screen input.
In your case, I suggest the same.. Which ACTIVE ADAPTER??. Maybe one of these:
http://www.newegg.com/Product/Product.aspx?Item=N82E16814999030 (this one is DP to DVI)
http://www.newegg.com/Product/Product.aspx?Item=N82E16815309008 (this one is mDP to DVI)
Actually, it's pretty simple, once you have the right adapter.. Just plug them in and configure..
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