Sorry for the noob hardware question here, but I have an 8800gts running two 24" monitors, I wanted to get another monitor and do the two portrait monitors on each side of the main as some have set up here. If I wanted to go with another card, would it be an issue to keep the 8800gts and add the ATI 4850, or would it cause problems having the two diff brands together and should just get another 8800gts?