XBMC + USB video adapter issues

I'm in the process of converting my old Dell dimension 4600 into a media PC running windows XP using XBMC. I was hoping to use an HDMI connection to be used with my 51" Panasonic TC-P50U50. My current video card (NVIDIA GEforce 5200 doesn't support HDMI, I thought the easiest way to solve this problem was to buy an external USB video Adapter (EVGA pure plus), which comes with DVI and HDMI outputs. I installed the drivers fine but when I tried to run XBMC, i get a black screen with an error message saying could not create GUI existing. I tried to go to EVGA website to update the drivers but I still get the same error.
Can anyone help me with this.
thanks