On your grounding qeustion, its very simple.
Your main PSU is plugged in with a 3 pin power connector into the wall, 1 of the 3 pins is the ground [PE wich stands for protected earth]
Through the 24pin ATX connector your board and other components or grounded with the case aswell, all basicly connected to 1 of the 3 pins that goes back through your PSU into the wall.
Wich one of the 3 pins it is i dont know because i only use EU plugs, in EU its the middle metal plate [not a pin]
Having an extra PSU on top of your PC is fine, again its grounded by the plug in the wall.
You dont need any extra grounding because all the other stuff is grounded by your main PSU allready.
Hope i kept it simple enough to easely understand it.
Great :) , Well that is what I thought all a long but I just could not settle it with myself lol and just wanted confirmation, but that's great, no extra cabled for me then. Good stuff :) Cheers budd.