hi i have an hp 8034n with athlon dual core 5000 with 3gb memory antec 500 watt power supply and an open pci express 16x slot the case is the media center type pc with the door flap for an external hard drive. i am looking for a video card i play a lot of flight sim games and like the detail of night scenery and water effects. i am caught between an evga 8600gt an ati 1650 or 1950 pro and a geforce 7900 .have heard that radeon has the edge on realism but i dont want a real power hungry card these cards wre suggested to me. need some help chosing the quality differences from people who maybe have good or bad reviews .each i'm sure have their little separate qualities.also something that is not a really big or long card as i am afraid it may hit the drive cage supports for the media bay . thanks for your help. am confused with all the choices.