I have a Precision T7500 workstation. I am looking at adding the 2nd CPU Riser Dell Part # H236D with Heatsink & Fan. Do I need anything else for the upgrade? I thought there was a rear fan or something that also has to be replaced when adding 2nd CPU riser but not sure. Also I see the riser has 2 plugs (pictured below), I'm assuming those plug into the stock power supply?