XBMC with black screen

I'm building up another machine, it being a small form factor so it has an ATI low profile GPU, to use as another HTPC for another room in my house, and connect to my file server to access the movies. Now i installed everything, but when playing the movies through XBMC, the video doesn't play, it just stays at 00:00:00 and i have a black screen for all movies. Now i get out of XBMC and play the movies through VLC, so a 480p, 720p, and 1080p, and they play just fine, so the GPU can handle the video just fine, but XBMC can't for some reason. Has anyone had this happen to them, or know of a way to fix it? Thanks