2000 Buick Regal speedometer rolled around to bottom

Are you still haveing problems with your speedometer? If you are you will need to take it to a buick dealer, and have them reprogram the computer to send it back to where it should be. Did you by any chance change the battery without hooking up a computer saver? That would be one of the reasons that I could think of for this problem. I had it happen to me the first week I bought my car.