Hello, My Mac Pro has been working fine since I got it a little over a year ago, but now the computer overheats 90% of the time if you run Mac OS X for more than 8-10 hours at a time. The computer runs fine under Windows XP, and can be left on as long as you want. I suspect it is the 3870 x2 not running cool under OS X. When I opened it up, all the red lights were on on both RAM risers, and the lights for "overtemp" on CPU A & B were also on. Sometimes, the grey "You need to restart your computer" screen comes on, other times the screen can't even finish loading it before the computer is completely dead. This can't be good for it, so I'd love to know of any solutions (other than stopping using OS X or removing the video card.) Thanks in advance!