For starters the "E" model has esata, optical audio, Firewire, and an extra network connector on the back panel. It has better heatsinks overall which will translate to higher and more stable overclocks. It has onboard buttons for power and reset and a more logical layout overall.
I am new to upgrading video cards but I am running into a problem. I have an Asus P5Q-E Core 2 Quad P45 Crossfirex Motherboard. I just bought an Visiontek HD3870 X2 video card. I am confused about how to plug in molex power cables. In the video card box is a y -cable that converts two traditional plugs into a 4 -port power plug that goes into 4 hole female connector or video card. But then there is a 6 holed female connector that needs power but the board only has another 4 hole male connector so there is a way to connect 4+2 connector to give you six. But the video card powers up but no display. I installed the ATI drivers before installing the video card but no results. So if this message was not thoroughly confusing and you understand what I am trying to say , I'd appreciate your help.
It sounds to me that you PSU is not capable of powering your system.
Could you please post your full system specs including the brand, wattage and +12v amperage of your PSU and any overclocks?
Also, in the future, please start a new thread in the proper section of the forum when you have a new question.
Most of the time, you will not get any help on your issue when posting in an unrelated thread that has been dead for three months.