some time boot up, some time will not boot up
I have power mac g5 (2003), it is 2.0GHZ dual processor and running 10.5.8, I press the power button and hear the chime sound every time, but some time will not boot up, when I hold down the power button to force it to shutdown and then restart( two or tree times), it always can boot up again , when it boot up the computer works good. no any problems. I try to reset PMU and PRAM and change the battery still can't fix the problem, please help.
Is this a good question?