I just set up my "new" mac pro mid 2010 quad core 2.88, and notice a very low sort of drone vibration from it, sort of like a military helicopter in the distance, and notice when it goes into sleep mode, and the large fan I can see through the grill stops spinning is when it goes silent. Is this normal? I would guess that there will be some noise from a pc like this, it is the biggest computer I have seen, it sees like a giant. I have it set up on a hard desktop, and it has a mechanical hard drive as the startup drive, I had planned to put in an SSD drive in it, and boost the ram. It is the pro with the 5770 card.