I have a Mid-2009 MacBook Pro 17" that works great. But when I turn it on or resume it from sleep, it shuts down immediately. I press the power button, it turns on and shows the apple logo - then shuts down like someone pulled the power. I do this about 4 or 5 times before it actually fully turns on. Sometimes a PRAM reset helps it in the second try, but I don't want to do this every single time I boot up. Any ideas?