Hi I have 2 powercolour HD4850 `s PowerColor PLAY! HD4850 512MB GDDR3 http://www.powercolor.com/eng/products_features.asp?ProductID=4506 I am having so much trouble to enable thease in crossfire mode, i have tried different bios`s and they just killed the card, so flashed back to original. Dose anybody have a new bios so thease cards will work with the latest drivers from ATI. Thankyou all, if you can help me with this problem you will save a life lol. Dazzy.