Are you sure about that model #? I can't find anything related to an Apple A3180, but I may have missed something. Can you verify that # or describe it ? Is it an all-metal (aluminum) case? Does it have a black bezel around the LCD? Or is it a plastic case? What ports are on the back?
I do find an A1083, however, Apple's model # for the 30" display. That display requires a digital signal, so it will not work at all from VGA, which is an analog signal. Also, since the 30" display has so many pixels, it requires a Dual-Link DVI connection.
Of all of Apple's LCD displays, only the very early models (M4451) will work with VGA. All the ones after that require a digital (DVI or Dual-Link DVI) signal. And several use the Apple Display Connector which eliminated the power brick by sending power from the display card, and it also sent USB over the same cable. One cable for everything.