Do you get a white screen, or a black screen? Do you hear a chime when you reset the PMU?
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Do you get a white screen, or a black screen? Do you hear a tone when you reset the PMU?
Test your RAM slots -- power on with one slot empty, and if that doesn't help, power on with the other slot empty. A lot of these machines have a failing slot, and when the bad slot is populated, the machine will have a black screen and show only minimal signs of life.
Do you get a white screen, or a black screen? Do you hear a chime when you reset the PMU?
Test your RAM slots -- power on with one slot empty, and if that doesn't help, power on with the other slot empty. A lot of these machines have a failing slot, and when the bad slot is populated, the machine will have a black screen and show only minimal signs of life.