I have a 550 watt PSU I got dirt cheap with a combo when I bought my rig. It is rate for up to 384 watts on the 12v rails, which is pretty darn good for a 550 watt PSU. I may decide to buy a lot of hard drives, or get a crossfire board down the road or something, and I would need more power for those sorts of things. I guess my questions are, what can be done with a second power supply? If I bought a cheap antec earthwatts, could I use it to run my hard drives, or maybe a second card (or the cpu?). Anybody know any thorough guides in the subject?