Okay, so I got a drive for my C64 today. No serial cable, but I took a power cable off an old PC of mine and powered it up. The green light came on, and the red light continued to blink continously as the drive span. When I put a disk in, it feels like it is stopping the drive from spinning, but it goes back to normal after I insert it all the way.

So, what's wrong? Do I need to recalibrate the drive heads or is it just like a matter of being hooked up to the computer? Or is it something even worse?