I am installing a computer right now and on its manual it says (vaguely) to hook up both the vga and dvi connections. i could do that, but i always thought it was one or the other. i have cables for both, and connections for both on the lcd and computer. currently its working fine afaik with just the dvi in. is the vga necissary? lcd is a http://www.newegg.com/Product/Product.aspx?Item=N82E16824009127