My pc has an AMD Athlon 4200 Dual Core (2.2Ghz) CPU and a MSI K9N4 Ultra motherboard NVIDIA nForce 500 chipset that was custom built for me in an Antec Mid Case 350W. I need to upgrade the graphics. What motherboard or graphics card would be compatible and support Windows Aero user interface? I'm upgrading from Win XP to Win7.