i7 3770K @ 4.5ghz, Asus P8Z77-V, 16GB 1866Mhz CL9, Sapphire Vapor-X 290X, Crucial M4 128GB, Seagate 3TB, Enermax Galaxy 1000W DXX, Windows 7 Ultimate x64
System was completely fine before upgrading from 6970 to 290x. Will prime95 test determine if system OC is stable before changing anything?