I've had my computer built for about a week now, and I didn't really notice this until a few nights ago. There's a sound that comes once in a while. It starts faint and grows louder. Then stops. Sometimes it'll repeat. It's a buzzing sound, not a clicking or rattling sound. It's not my exhaust fan because I unplugged it. So I've narrowed it down to possibly being my Zalman 7700 or the power supply. I'm leaning towards the power supply, which is an Antec Smart Power 2.0 400 watts. Does anyone know what it could be? Or if I should even worry about it? It's kinda annoying. 
