I have two monitors, a DELL S2230MX, and a DELL D2015H. I have my DELL S2230MX connected with a vga cable, and my DELL D2015H connected with a dvi adapter which adapts to a end that is red, i dont know what thats called. So my DELL D2015H says that there is no signal coming from my computer, but i have it plugged into my computer.. Any help?