OK, I'm an idiot.... I didn't hook up the extra 12V ATX power connector. So, another important question: I've removed the HSF from the CPU. Should I / must I clean it and apply new thermal paste? I know the answer to this is almost certainly "yes," but since the CPU hasn't had power yet, it hasn't been heated, so maybe the same thermal pad will work? Some is stuck to the CPU, but it hasn't "melted" yet. Furthermore, it's a PIB, so will using third-party paste void my warranty?