If you still get nothing, it could be the power supply, but a bad power supply will usually not make any 'clicks' when you plug the power cord in.Īfter that, it gets to be not worth it to fix, unless you have a complete spare PowerMac for parts.

If it still doesn't start, then try swapping the bottom processor into the top slot. Your PowerMac will run with only one processor, but it must be in the top slot. If you still get nothing, Try removing the bottom processor. Wait another 10 seconds, then plug the power cord in. Press the PMU reset button once only (it's not near the battery, but is under the RAM slots near the bottom of the logic board), Do not press a second time, as you may crash the PMU chip. A new battery should be between 3.6 and 3.7 volts.) Put your tested battery back in, and wait 10 seconds. To add to the faulty keyboard and swollen battery, it turns out my MacBook Pro has a third failure: a logic board fault. If you lose the use of another component of your computer, such as the display, battery, or even power, and replacing the apparently non-working part didn't fix the problem. Any one of these components can fail and leave the others intact. Stuttering: When a graphics card starts going bad, you might see visual stuttering/freezing on the screen. Because there are many components of the logic board, many possible symptoms indicate logic board failure. Test it for more than 3.3 volts (an almost new battery does not mean it's good - test it with a voltmeter for at least 3.3 volts. Here are some early warning signs of video card failure. If that doesn't help, disconnect your power cord, and remove that PRAM battery.

Mac logic board failure symptoms