SolidWorks 2014 Professional 64 bit

Core I-7 2.8GH quad core

Does the final render window need to be always on top? It can be minimized so other work can be done, but does that slow it down? It's using almost 90% of the CPU, with the rest being used by Internet, e-mail, SolidWorks in the background of course, plus background stuff. It's taking over 30 minutes to render a simple assembly, using Maximum quality.