... so, ¿is this normal? I got my 2009 2.66Ghz Quad Mac Pro with the ATI4870 graphics card a few weeks ago. I noticed that when the machine is off, but connected to an ungrounded (or shared with other devices) electric outlet, the whole case gets electrified and power leaks to it. If one's touching it the machine and making direct contact with the floor, it gives small-pulsing-continuous electric shocks. I reported it to Apple and took it to an Apple Service center, where they have a robust grounded installation, so nothing showed up. I worry that - regardless of the electrical installation (my studio's electric ground has been now reinforced with a direct ground from the MP's outlet), there is something wrong with the internal power source unit - e.g. not being properly isolated from the rest of the case - and/or that this leakage might damage some of the electronics of the machine. What do you think? Has anyone else come across this? Thanks!