My step father who has taught me alot since I was three had given me an Asrock 939 Dual Vista motherboard. He builds alot of computers and I kinda want to surprise him on fathers day to show how much I learned from him. My question really is more like advice and some expertise help. Asrock 939 dual vista, Amd 64 processor , I know tomorrow I am going to order 4 gig of ddr400 that uses less than 2.7v. I have a atx 650watt power supply. I alrady have that in the tower and have fans and led lights ready to install. Ok.... is the Nividia Quadro fx 3800 1gb a good pci-e card for this system? What would be the best Hard drive I could use? I already have the cd/dvd rom. Also what would be the best o/s I could use. This computer will be used so I can play Guild Wars 2 and such with him on weekends and some rainy days. Any info will be greatly appreciated. Thank you.