8600GT Graphics Card & External Monitor

Discussion in 'MacBook Pro' started by Mark 618, May 19, 2008.

  1. Mark 618 macrumors newbie

    Apr 29, 2008
    I was reading some other posts where a reference was made to the affect connecting an external monitor (through the DVI connection) has on the video card in the MBP (either the 8600 GT 256 mb or 512 mb). The comment made was that connecting the external monitor would direct half of the vRAM to operating the external monitor thereby leaving the other half of the vRAM for use by the computer (so for a 256 mb card 128 mb would drive the external monitor and 128 mb would be left for system requirements)

    If the MBP will be mostly connected to an external monitor would it be advisable to get the system configuration with the 8600 GT 512 mb video card as that would have 256 mb directed to driving the external monitor and leave 256 mb for use by the computer?

    I was also reading a thread where there was some discussion about the capacity of the 8600 GT card as the 128 bit memory bus is a limiting factor. It was indicated that the 128 memory bus functions well with 256 mb of vRAm but the card is not fast enough to handle 512 mb of vRAM. In the case where an external monitor is connected how does that affect the performance of the video card?
  2. alphaod macrumors Core


    Feb 9, 2008
    The amount of VRAM doesn't affect the video as much as the speed of graphics card. Basically if you connect an external the card has to drive both the external and the internal, so you get half the performance on each depend on the resolutions you're using; with regard to VRAM, well it's not always half; if you're running graphics intensive stuff on your external, more VRAM will be allocated to the external.

Share This Page