Thank you, Most likely if the mac wasnt powered on it that time one of two issues occured.
Either the pram battery has failed or it needs to be reset. Most likely due to the age of that unit and it sitting for that much time without an electrical current, the battery failed and needs to be replaced.
But lets try to reset it first, heres how
Shut down your Mac.
Locate the following keys on the keyboard: Option, Command (⌘), P, and R. You will need to hold these keys down simultaneously in step 4.
Turn on your Mac.
Immediately press and hold the Option-Command-P-R keys. You must press this key combination before the gray screen appears.
Continue holding the keys down until your Mac restarts, and you hear the startup sound for the second time.
Release the keys.
If that wont get the machine to show any signs of life. Then you need to replace the pram battery.. Its a process, Heres how.
And here is where you can purchase a new pram battery. http://amzn.to/1XluHLV
If you have further questions, let me know.
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