Will changing the video card cause any set-up problems with your software i.e. DirectX config, or can I swap to another card without any foreseeable problems.

This should not be a problem as long as correct drivers for the new board are installed. Note that EthoVision 2 and 3 does require a video card, if there is only internal video present it will not work correctly. You can use EthoVision XT with internal video.

EthoVision 2.3, EthoVision 3, EthoVision XT 4, EthoVision XT 5, EthoVision XT 6, EthoVision XT 7, EthoVision XT 8