I have a chance to buy a Mac Pro 3,1 at a really good price. I was thinking of using it to replace my Mac Mini server so I can get ride of the external drives hanging off the Mini. The bays in the MP would give me more than enough space and I would only need to connect external drives for backup. I know power consumption will be higher. Heat won't be an issue as it will be in a cool basement area. How much power does a MP really draw with 2 or 3 hard drives? Any other issues I need to consider?