Power Cord Issue

Hey guys, almost had a heart attack tonight. Recently my macbook's power cord started acting temperamental, there's a loose wire near the mag connector.

Anyway, my roommate just got a brand new charger for his macbook. My laptop ran out of juice so I grabbed his to get some charge. As soon as I hooked it up, my HDD light started flickering and I could hear the drive trying to spin but it kept shutting off. The light on the charger stayed green as well. Holding down the power button and closing the lid did nothing.

I panicked and decided the best thing to do would be to pull the drive. After doing so, the symptoms persisted so I felt a little better knowing my HDD wasn't a paper weight. I then decided to try my power cord. I plugged it in and my macbook started up as if nothing happened.

My only guess is that the computer registered that there was power but it wasn't enough juice to actually start the thing up. Has anyone had or heard anything about this issue? I've used plenty of different power cords on my laptop, old and new, this hasn't happened before!

Was the power supply for the same model they do have different watt ratings for various models.

Guess what? The Apple store gave him a macbook charger instead of a macbook pro charger, that explains why my machine wouldn't boot when flat dead. Thanks for the heads up, when I get my charger replaced I'll be sure it's an 85W and not a 60W.

As a side question, is my roommate harming his macbook pro by running it with a 60W charger?